Every national soil interpretation, in plain language

URB/REC - Urban and Recreational Land Uses

Camp areas are tracts of land used intensively as sites for tents, trailers, campers, and the accompanying activities of outdoor living. Camp areas require site preparation, such as shaping and leveling the tent and parking areas, stabilizing roads and intensively used areas, and installing sanitary facilities and utility lines. Camp areas are subject to heavy foot traffic and some vehicular traffic.

The ratings are based on the soil properties that affect the ease of developing camp areas and the performance of the areas after development. Slope, stoniness, and depth to bedrock or a cemented pan are the main concerns affecting the development of camp areas. The soil properties that affect the performance of the areas after development are those that influence trafficability and promote the growth of vegetation, especially in heavily used areas. For good trafficability, the surface of camp areas should absorb rainfall readily, remain firm under heavy foot traffic, and not be dusty when dry. The soil properties that influence trafficability are texture of the surface layer, depth to a water table, ponding, flooding, saturated hydraulic conductivity (Ksat), and large stones. The soil properties that affect the growth of plants are depth to bedrock or a cemented pan, saturated hydraulic conductivity (Ksat), and toxic substances in the soil.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect development. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Deep infiltration systems are stormwater management practices that are placed 3 to 5 feet in the ground, depending on the application. These systems include rain gardens, bioretention basins, and infiltration basins. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. There should be little or no ponding at the surface. The water should infiltrate into the surrounding soil in 24 to 48 hours. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water.

Some soils are underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system. In these soils the deep infiltration system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified infiltration system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one indicated for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit. The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Wastewater includes municipal and food-processing wastewater and effluent from lagoons or storage ponds. Municipal wastewater is the waste stream from a municipality. It contains domestic waste and may contain industrial waste. It may have received primary or secondary treatment. It is rarely untreated sewage. Food-processing wastewater results from the preparation of fruits, vegetables, milk, cheese, and meats for public consumption. In places it is high in content of sodium and chloride. The effluent in lagoons and storage ponds is from facilities used to treat or store food-processing wastewater or domestic or animal waste. Domestic and food-processing wastewater is very dilute, and the effluent from the facilities that treat or store it commonly is very low in content of carbonaceous and nitrogenous material; the content of nitrogen commonly ranges from 10 to 30 milligrams per liter. The wastewater from animal waste treatment lagoons or storage ponds, however, has much higher concentrations of these materials, mainly because the manure has not been diluted as much as the domestic waste. The content of nitrogen in this wastewater generally ranges from 50 to 2,000 milligrams per liter. When wastewater is applied, checks should be made to ensure that nitrogen, heavy metals, and salts are not added in excessive amounts. Disposal of wastewater by irrigation not only disposes of municipal wastewater and wastewater from food-processing plants, lagoons, and storage ponds but also can improve crop production by increasing the amount of water available to crops. The ratings are based on the soil properties that affect the design, construction, management, and performance of the irrigation system. The properties that affect design and management include the sodium adsorption ratio, depth to a water table, ponding, available water capacity, saturated hydraulic conductivity (Ksat), slope, and flooding. The properties that affect construction include stones, cobbles, depth to bedrock or a cemented pan, depth to a water table, and ponding. The properties that affect performance include depth to bedrock or a cemented pan, bulk density, the sodium adsorption ratio, salinity, reaction, and the cation-exchange capacity, which is used to estimate the capacity of a soil to adsorb heavy metals. Permanently frozen soils are not suitable for disposal of wastewater by irrigation. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect agricultural waste management. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Rapid infiltration of wastewater is a process in which wastewater applied in a level basin at a rate of 4 to 120 inches per week percolates through the soil. The wastewater may eventually reach the ground water. The application rate commonly exceeds the rate needed for irrigation of cropland. Vegetation is not a necessary part of the treatment; thus, the basins may or may not be vegetated. The thickness of the soil material needed for proper treatment of the wastewater is more than 72 inches. As a result, geologic and hydrologic investigation is needed to ensure proper design and performance and to determine the risk of ground-water pollution. Soil properties are important considerations in areas where soils are used as sites for the treatment and disposal of organic waste and wastewater. Selection of soils with properties that favor waste management can help to prevent environmental damage. Municipal wastewater is the waste stream from a municipality. It contains domestic waste and may contain industrial waste. It may have received primary or secondary treatment. It is rarely untreated sewage. Food-processing wastewater results from the preparation of fruits, vegetables, milk, cheese, and meats for public consumption. In places it is high in content of sodium and chloride. The effluent in lagoons and storage ponds is from facilities used to treat or store food-processing wastewater or domestic or animal waste. Domestic and food-processing wastewater is very dilute, and the effluent from the facilities that treat or store it commonly is very low in content of carbonaceous and nitrogenous material; the content of nitrogen commonly ranges from 10 to 30 milligrams per liter. The wastewater from animal waste treatment lagoons or storage ponds, however, has much higher concentrations of these materials, mainly because the manure has not been diluted as much as the domestic waste. The content of nitrogen in this wastewater generally ranges from 50 to 2,000 milligrams per liter. When wastewater is applied, checks should be made to ensure that nitrogen, heavy metals, and salts are not added in excessive amounts. The ratings are based on the soil properties that affect the risk of pollution and the design, construction, and performance of the system. Depth to a water table, ponding, flooding, and depth to bedrock or a cemented pan affect the risk of pollution and the design and construction of the system. Slope, stones, and cobbles also affect design and construction. Saturated hydraulic conductivity (Ksat) and reaction affect performance. Permanently frozen soils are unsuitable for waste treatment. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect agricultural waste management. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Embankments, dikes, and levees are raised structures of soil material, generally less than 20 feet high, constructed to impound water or to protect land against overflow. Embankments that have zoned construction (core and shell) are not considered. The soils are rated as a source of material for embankment fill. The ratings apply to the soil material below the surface layer to a depth of about 5 feet. It is assumed that soil layers will be uniformly mixed and compacted during construction. The ratings do not indicate the suitability of the undisturbed soil for supporting the embankment. Soil properties to a depth even greater than the height of the embankment can affect performance and safety of the embankment. Generally, deeper onsite investigation is needed to determine these properties. Soil material in embankments must be resistant to seepage, piping, and erosion and have favorable compaction characteristics. Unfavorable features include less than 5 feet of suitable material and a high content of stones or boulders, organic matter, or salts or sodium. A high water table affects the amount of usable material. It also affects trafficability. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

AGR - Agriculture DHS - Department of Homeland Security ENG - Engineering

The ratings for Ground Penetrating Radar Penetration are based on the soil properties that affect the penetration of GPR signals into the soil. Soil properties affecting the penetration are considered. In many soils, high amounts of signal attenuation severely restrict radar penetration depths and limit the suitability of GPR for a large number of applications. The ratings are for soils in their natural condition and do not consider present land use. The properties that affect signal penetration include clay content, water saturation, organic matter content, carbonate content, sulfate content, salinity, and sodicity. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Very high penentration" indicates that the soil has features that are very favorable for the specified use. Good performance can be expected. "High penetration" grading to "Very low penetration" indicates that the soil has features that are less favorable for the radar penetration. "Unsuited" indicates that the soil has features that will not let radar penetrate. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating. A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Deep infiltration systems are stormwater management practices that are placed 3 to 5 feet in the ground, depending on the application. These systems include rain gardens, bioretention basins, and infiltration basins. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. There should be little or no ponding at the surface. The water should infiltrate into the surrounding soil in 24 to 48 hours. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water.

Some soils are underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system. In these soils the deep infiltration system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified infiltration system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one indicated for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit. The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Shallow infiltration systems are stormwater management practices that are placed 1 to 3 feet in the ground, depending on the application. These systems include pervious pavement, buffer strips, filter strips, and vegetated swales. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated by an area, such as a parking lot, from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. There should be little or no ponding at the surface. The water should infiltrate into the surrounding soil in 24 to 48 hours. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water.

Soils underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system may adversely affect water quality and public health. In these soils the shallow infiltration system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified infiltration system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one listed for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit.

The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation evaluates a soil's limitation(s) for installation and use of irrigation systems. This interpretation is for non-specific irrigation methods and is intended to provide initial planning information. If the type of irrigation system has been determined, additional interpretations provide more specific information. This interpretation does not apply if the crop planned for irrigation is rice or other crops (such as cranberries) with unique plant physiological characteristics. The ratings are for soils in their natural condition and do not consider present land use. Irrigation systems are used to provide supplemental water to crops, orchards, vineyards, and vegetables in areas where natural precipitation will not support desired production of crops being grown. The soil properties and qualities important in design and management of irrigation systems are sodium adsorption ratio, depth to high water table, available water holding capacity, saturated hydraulic conductivity (Ksat), slope, calcium carbonate content, ponding, and flooding. Soil properties and qualities that influence installation are stones, depth to bedrock or cemented pan, and depth to a high water table. The properties and qualities that affect performance of the irrigation system are depth to bedrock or to a cemented pan, the sodium adsorption ratio, salinity, and soil reaction. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the interpretation. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). Rating class terms indicate the extent to which the soils are limited by the soil features that affect the soil interpretation. Verbal soil rating classes are based on the highest numerical rating for the most limiting soil feature(s) considered in the rating process. "Not limited" (numerical value for the most restrictive feature = 0.00) indicates that the soil has no limiting features for the specified use. "Somewhat limited" (numerical value for the most restrictive feature =.01 to.99) indicates that the soil has limiting features for the specified use that can be overcome with proper planning, design, installation, and management. The effort required to overcome a soil limitation increases as the numerical rating increases. "Very limited" (numerical value for the most restrictive feature = 1.00) indicates that the soil has one or more very limiting features that can only be overcome with special planning, major soil modification, special design, or significant management practices. Lesser soil restrictive features have a lower numerical value than the maximum used to rate the soil, and they are identified to provide the user with additional information about soil limitations for the specific use. Lesser soil restrictive features also need to be considered in planning, design, installation, and management. The results of this interpretation are not designed or intended to be used in a regulatory manner. The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Application of sewage sludge not only disposes of waste material but also can improve crop production by increasing the supply of nutrients in the soils where the material is applied. Sewage sludge is the residual product of the treatment of municipal sewage. The solid component consists mainly of cell mass, primarily bacteria cells that developed during secondary treatment and have incorporated soluble organics into their own bodies. The sludge has small amounts of sand, silt, and other solid debris. The content of nitrogen varies. Some sludge has constituents that are toxic to plants or hazardous to the food chain, such as heavy metals and exotic organic compounds, and should be analyzed chemically prior to use. The content of water in the sludge ranges from about 98 percent to less than 40 percent. The sludge is considered liquid if it is more than about 90 percent water, slurry if it is about 50 to 90 percent water, and solid if it is less than about 50 percent water. The ratings are based on the soil properties that affect absorption, plant growth, microbial activity, erodibility, the rate at which the sludge is applied, and the method by which the sludge is applied. The properties that affect absorption, plant growth, and microbial activity include saturated hydraulic conductivity (Ksat), depth to a water table, ponding, the sodium adsorption ratio, depth to bedrock or a cemented pan, available water capacity, reaction, salinity, and bulk density. The wind erodibility group, soil erosion factor K, and slope are considered in estimating the likelihood that wind erosion or water erosion will transport the waste material from the application site. Stones, cobbles, a water table, ponding, and flooding can hinder the application of sludge. Permanently frozen soils are unsuitable for waste treatment. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect agricultural waste management. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Lined retention systems are stormwater management practices that are placed 3 to 5 feet in the ground, depending on the application. An impervious liner, made of rubber or clay, is used to retain water and thus to maintain hydrophytic vegetation. These systems are meant to be used where the hydrology will not allow other systems, but the slope and bedrock depth are favorable. These systems include retention basins and intermittent wetlands. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated by an area, such as a parking lot, from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. Water should not be at the surface continuously, but a water table within the depth of the system is needed to allow the growth of hydrophytic vegetation. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Some land shaping may be needed to allow stormwater runoff to accumulate in the system. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water

Soils that are underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system may adversely affect water quality and public health. In these soils the lined retention system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one listed for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit.

The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The application of manure and food-processing waste not only disposes of waste material but also can improve crop production by increasing the supply of nutrients in the soils where the material is applied. Manure is the excrement of livestock and poultry, and food-processing waste is damaged fruit and vegetables and the peelings, stems, leaves, pits, and soil particles removed in food preparation. The manure and food-processing waste are solid, slurry, or liquid. Their nitrogen content varies. A high content of nitrogen limits the application rate. Toxic or otherwise dangerous wastes, such as those mixed with the lye used in food processing, are not considered in the ratings. The ratings are based on the soil properties that affect absorption, plant growth, microbial activity, erodibility, the rate at which the waste is applied, and the method by which the waste is applied. The properties that affect absorption include saturated hydraulic conductivity (Ksat), depth to a water table, ponding, the sodium adsorption ratio, depth to bedrock or a cemented pan, and available water capacity. The properties that affect plant growth and microbial activity include reaction, the sodium adsorption ratio, salinity, and bulk density. The wind erodibility group, soil erosion factor K, and slope are considered in estimating the likelihood that wind erosion or water erosion will transport the waste material from the application site. Stones, cobbles, a water table, ponding, and flooding can hinder the application of waste. Permanently frozen soils are unsuitable for waste treatment. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect agricultural waste management. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is designed to evaluate the potential for nitrate-nitrogen to be transmitted through the soil profile below the root zone by percolating water under irrigated conditions. Leaching nitrates have the potential to contaminate shallow and deep aquifers used for drinking water. The ratings are based on inherent soil and climate properties that affect nitrate leaching and do not account for management practices, such as crop rotation, rates and timing of nitrogen fertilizer applications, and management of irrigation water.

The following soil and climate factors are used in the interpretation criteria:

1. Mean annual precipitation minus potential evapotranspiration - This factor provides an estimate of the amount of water that is available to move through the soil profile on an annual basis from precipitation. Potential evaporation is estimated from mean annual air temperature using an algorithm (developed by the National Soil Survey Center) that employs the Hamon potential evapotranspiration method.

2. Water travel time through the entire soil profile - This factor uses the saturated hydraulic conductivity (Ksat) and thickness of each soil horizon to estimate the number of hours that would be required for a given volume of water to move through the entire soil profile. One advantage of this method for estimating the rate of water movement is that the properties and thickness of each soil horizon are accounted for instead of using an average saturated hydraulic conductivity for the entire profile. This method accounts for subtle differences between soils in texture, structure, horizon thickness, and depth to water-restricting layers.

3. Available water capacity - This factor accounts for the cumulative amount of water available to plants that the entire soil profile can hold at field capacity to a depth of 150 cm. The more water the soil profile can hold, the less water is available for deep leaching.

4. Depth to and duration of a water table - This factor uses a water table index based on the minimum average depth to a water table and the number of months that the water table is present during the period from April through October. The factor is used to account for the loss of nitrates to the atmosphere as nitrous oxide or nitrogen gas due to denitrification under anaerobic conditions caused by water saturation. The higher the water table and the longer its duration, the larger the quantity of nitrates that would potentially be lost to the atmosphere and therefore would not be available for deep leaching.

5. Slope gradient adjusted for hydrologic soil group - The steeper the slope gradient, the higher the potential for surface runoff and the lower the amount of water available to move through the soil profile. The following adjustments are made to the slope gradient by hydrologic group to account for differences in potential for surface runoff:

Hydrologic group A-slope % x 0.75 Hydrologic group B-slope % x 0.85 Hydrologic group C-slope % x 0.95 Hydrologic group D-no adjustment

The ratings are both verbal and numerical. The ratings for Nitrate Leaching Potential, Irrigated Areas, are calculated as follows:

1. The Water Travel Time subrule is weighted by multiplying by 0.60. 2. The Available Water Capacity subrule is weighted by multiplying by 0.40. 3. The sum of these two weighted subrules results in a value between 0.00 and 1.00. 4. Adjustments are then made for water table depth and duration and for slope gradient adjusted for hydrologic group. The sum of the values from these subrules is subtracted from the sum in step 3 above. The maximum reduction is 0.50 for the water table index subrule and 0.30 for the slope gradient subrule. 5. A final positive adjustment is made for the Mean Annual Precipitation minus Potential Evapotranspiration subrule. The maximum addition is 0.60.

The following rating classes for Nitrate Leaching Potential, Irrigated, are assigned based on the final calculation from the factors above:

Low: 0.00 to 0.25 Moderate: 0.26 to 0.50 Moderately high: 0.51 to 0.75 High: 0.76 to 1.00

The ratings indicate the potential for nitrate leaching below the root zone, based on inherent soil and climate properties and application of irrigation water. A "low" rating indicates a low potential for leaching of nitrates below the root zone. A "high" rating indicates a high potential for leaching of nitrates below the root zone. The "moderate" and "moderately high" ratings indicate intermediate potential.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is designed to evaluate the potential for nitrate-nitrogen to be transmitted through the soil profile below the root zone by percolating water under nonirrigated conditions. Leaching nitrates have the potential to contaminate shallow and deep aquifers used for drinking water. The ratings are based on inherent soil and climate properties that affect nitrate leaching and do not account for management practices, such as crop rotation and rates and timing of nitrogen fertilizer applications.

The following soil and climate factors are used in the interpretation criteria:

1. Mean annual precipitation minus potential evapotranspiration - This factor provides an estimate of the amount of water that is available to move through the soil profile on an annual basis. Potential evaporation is estimated from mean annual air temperature using an algorithm (developed by the National Soil Survey Center) that employs the Hamon potential evapotranspiration method.

2. Water travel time through the entire soil profile - This factor uses the saturated hydraulic conductivity (Ksat) and thickness of each soil horizon to estimate the number of hours that would be required for a given volume of water to move through the entire soil profile. One advantage of this method for estimating the rate of water movement is that the properties and thickness of each soil horizon are accounted for instead of using an average saturated hydraulic conductivity for the entire profile. This method accounts for subtle differences between soils in texture, structure, horizon thickness, and depth to water-restricting layers.

3. Available water capacity - This factor accounts for the cumulative amount of water available to plants that the entire soil profile can hold at field capacity to a depth of 150 cm. The more water the soil profile can hold, the less water is available for deep leaching.

4. Depth to and duration of a water table - This factor uses a water table index based on the minimum average depth to a water table and the number of months that the water table is present during the period from April through October. The factor is used to account for the loss of nitrates to the atmosphere as nitrous oxide or nitrogen gas due to denitrification under anaerobic conditions caused by water saturation. The higher the water table and the longer its duration, the larger the quantity of nitrates that would potentially be lost to the atmosphere and therefore would not be available for deep leaching.

5. Slope gradient adjusted for hydrologic soil group - The steeper the slope gradient, the higher the potential for surface runoff and the lower the amount of water available to move through the soil profile. The following adjustments are made to the slope gradient by hydrologic group to account for differences in potential for surface runoff:

Hydrologic group A-slope % x 0.75 Hydrologic group B-slope % x 0.85 Hydrologic group C-slope % x 0.95 Hydrologic group D-no adjustment The ratings are both verbal and numerical. The ratings for Nitrate Leaching Potential, Nonirrigated Areas, are calculated as follows:

1. The Mean Annual Precipitation minus Potential Evapotranspiration subrule is weighted by multiplying by 0.60. 2. The Water Travel Time subrule is weighted by multiplying by 0.25. 3. The Available Water Capacity subrule is weighted by multiplying by 0.15. 4. The sum of these three weighted subrules results in a value between 0.00 and 1.00. 5. Adjustments are then made for water table depth and duration and for slope gradient adjusted for hydrologic group. The sum of the values from these subrules is subtracted from the sum in step 4 above. The maximum reduction is 0.50 for the water table index subrule and 0.30 for the slope gradient subrule.

The following rating classes for Nitrate Leaching Potential, Nonirrigated Areas, are assigned based on the final calculation from the factors above:

Low: 0.00 to 0.25 Moderate: 0.26 to 0.50 Moderately high: 0.51 to 0.75 High: 0.76 to 1.00

The ratings indicate the potential for nitrate leaching below the root zone, based on inherent soil and climate properties. A "low" rating indicates a low potential for leaching of nitrates below the root zone. A "high" rating indicates a high potential for leaching of nitrates below the root zone. The "moderate" and "moderately high" ratings indicate intermediate potential.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

URB/REC - Urban and Recreational Land Uses

Off-road motorcycle trails are intended primarily for recreational use. They require little or no site preparation. They are not covered with surfacing material or vegetation. Considerable compaction of the soil material is likely.

The ratings are based on the soil properties that influence erodibility, trafficability, dustiness, and the ease of revegetation. These properties are stoniness, slope, depth to a water table, ponding, flooding, and texture of the surface layer.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

In this process wastewater is applied to the upper reaches of sloped land and allowed to flow across vegetated surfaces, sometimes called terraces, to runoff-collection ditches. The length of the run generally is 150 to 300 feet. The application rate ranges from 2.5 to 16.0 inches per week. It commonly exceeds the rate needed for irrigation of cropland. The wastewater leaves solids and nutrients on the vegetated surfaces as it flows downslope in a thin film. Most of the water reaches the collection ditch, some is lost through evapotranspiration, and a small amount may percolate to the ground water. Wastewater includes municipal and food-processing wastewater and effluent from lagoons or storage ponds. Municipal wastewater is the waste stream from a municipality. It contains domestic waste and may contain industrial waste. It may have received primary or secondary treatment. It is rarely untreated sewage. Food-processing wastewater results from the preparation of fruits, vegetables, milk, cheese, and meats for public consumption. In places it is high in content of sodium and chloride. The effluent in lagoons and storage ponds is from facilities used to treat or store food-processing wastewater or domestic or animal waste. Domestic and food-processing wastewater is very dilute, and the effluent from the facilities that treat or store it commonly is very low in content of carbonaceous and nitrogenous material; the content of nitrogen commonly ranges from 10 to 30 milligrams per liter. The wastewater from animal waste treatment lagoons or storage ponds, however, has much higher concentrations of these materials, mainly because the manure has not been diluted as much as the domestic waste. The content of nitrogen in this wastewater generally ranges from 50 to 2,000 milligrams per liter. When wastewater is applied, checks should be made to ensure that nitrogen, heavy metals, and salts are not added in excessive amounts. The ratings are for waste management systems that not only dispose of and treat wastewater but also are beneficial to crops. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect agricultural waste management. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

URB/REC - Urban and Recreational Land Uses

Paths and trails for hiking and horseback riding should require little or no slope modification through cutting and filling.

The ratings are based on the soil properties that affect trafficability and erodibility. These properties are stoniness, depth to a water table, ponding, flooding, slope, and texture of the surface layer.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

PFAS

PFAS Attenuation in Soils

PFAS chemicals are a wide variety of manmade compounds that have been entered into the environment for many different reasons. Since the molecules are generally anionic, they have some degree of mobility in soils. The research illustrates a variety of interactions between PFAS and soil constituents that can lead to the movement of PFAS with water being slowed or perhaps even stopped at least temporarily. Li et al (2018) report on several mechanisms of sorption-desorption in their review of the literature. These mechanisms conceptually include hydrophobic interaction with organic matter, ligand bridging through divalent cations, electrostatic interaction with positive charges on mineral surfaces and some organic matter, and electrostatic interaction with oxides (Li et al. 2018). In their study of differing sizes of PFAS molecules and differing soil properties, Nguyen et al. (2020) concluded that many soil properties need to be evaluated in studying PFAS mobility in soils and also the size and shape of the PFAS molecules play a role in attenuation. They also hypothesize that some PFAS molecules may be trapped in soil micropores and the volume of soil available for sorption-desorption must be considered in the field (Nguyen et al. 2020). Brusseau (2019) reports that adsorption at air-water interfaces can cause significant retention of PFAS spatially and temporally. The amount of interfacial adsorption depends upon the volume of soil present (Brusseau, 2019). Recently, there has been study of a "non-extractable residue" (NER) of PFAS chemicals (Gassmann et al. 2020) but the mechanism of occlusion remains obscure. Gassmann et al. 2020) have postulated that the PFAS molecules may occasionally be physically entrapped into the soil organic matter matrix, rather than adsorbed on the surface. Uwayezu et al. (2019) examined the interactions between PFOS isomers and goethite in varying regimes of pH, organic matter and sulphate. As pH was increased from 4.36 sorption of PFOS decreased due to the changing of the charge of organic matter. Sorption of PFOS in the pH range less than 7.5 is thought to be due to electrostatic attractions between iron minerals such as goethite surfaces and the PFOS anions (Uwayezu et al. 2019). Campos-Pereira et al. (2020) also examined the adsorption of PFAS by poorly crystalline ferrihydrite as a function of pH and phosphate concentration.

PFAS Attenuation Model

Many of the parameters that address the mobility of PFAS in soils that have been examined in the literature are data elements in the soil survey database. Thus, the database should prove useful in tying the relative mobility of PFAS to soil and site properties. Keep in mind that the goal is to provide an array of the relative ability of soils to hold PFAS and not a quantitative estimate at this time. The model is focused on an eight-carbon chain molecule having a carboxyl functional group.

The overall rule-based fuzzy logic model contains four sub-rules. First, the surface area of unsaturated soil is estimated, as is suggested by the work of Nguyen et al. (2020) and Brusseau (2019). This capacity factor is considered as the surface area of soil throughout the year that exists on a one-centimeter square of soil multiplied by the depth, in cm, to the saturated zone or bedrock summed over twelve months. The surface area of unsaturated soil membership function evaluates a crude estimate of the surface area of unsaturated soil available for sorption-desorption processes. The estimate of surface area is calculated from the proportion of the fine earth fraction multiplied by the clay percentage. The frame of reference is limited to 200 cm, which is the depth of inference for the soil survey. Shallow bedrock or water restrictive layers will decrease the volume of unsaturated soil. The conceptual unit is a vertical rectangular prism 1cm x 1cm x the estimated depth of reference. This surface area is summed over the 12 months of the year. Thus, a soil averaging 60 percent clay through 200 cm depth, having no saturation, restriction, or rock fragments, would have a relative surface rating of 960. An impervious surface or water table at or above the surface for the duration of the year is defined as 0.

The next sub-rule considers the anion exchange capacity of the amorphous materials in soils and the organic matter content. This is pH dependent charge that is manifested at low pH. Some soil orders, such as Andisols, are characterized by typically having a large concentration of poorly crystalline materials while young soils, such as Inceptisols are generally low in amorphous materials. This sub-rule is suggested by the work of Uwayezu et al. (2019) and Gassmann et al. (2020). The amorphous materials sub-rule is composed of several membership functions that describe differing soil conditions. Since the content of iron and aluminum oxides is not currently well-populated in the database, Soil Taxonomic mineralogy family classes are used to fill the gaps. Soils in Taxonomic mineralogy families of "amorphic", "halloysitic", "ferruginous", "kaolinitic", "parasesquic", "oxidic", "ferritic", "gibbsitic", "sesquic", "allitic", "ferrihydritic", "glassy", "parasesquic", or "isotic" are assumed to contain significant amounts of amorphous materials that can have anion exchange capacity at low pH. The soil pH is evaluated over the range from 4.5 to 5.0 for its effect on anion exchange. Taxonomic order is used as a proxy for free iron oxide content, assuming that more highly weathered soils have more free iron oxides than less weathered soils and may have anion exchange if the pH is low. The soil orders are arrayed as follows: Andisols greater than Spodosols equal to Oxisols greater than Ultisols equal to Histosols greater than Alfisols greater than Inceptisols greater than Entisols. The soil orders of Gelisols, Mollisols, Vertisols, Aridisols are not considered to have anion exchange and because of this will not attenuate PFAS by this mechanism. Campos-Pereira et al. (2020) observed adsorption of PFAS on poorly crystalline iron oxides when the pH was below 7 for most PFAS species. This suggests pH dependent anion exchange may persist in soils when the pH is above 4.5.

For the third sub-rule, a large body of literature examines the interaction between PFAS materials and soil organic matter. Higgins and Luthy (2006), Millinovic et al. (2015), Li et al. (2012), and Zhu et al. (2021) all conclude that the organic materials in soil can sorb PFAS. Thus, a soil organic matter sub-rule provides a relative measure of the organic matter content of the profile of soils, in kilograms organic matter per meter square of soil. Soil organic matter content is highly correlated with PFAS attenuation. The type of organic matter likely also has some bearing, but the current model is constrained to only look at the estimate of the total amount. The organic matter content is evaluated over the range of 5 kg/m2 to 50 kg/m2. Higher organic matter contents are assumed to cause more attenuation of PFAS.

The fourth sub-rule considers the interactions between temperature, land surface slope, and the annual fluctuations of a water table on PFAS mobility. This subrule consists of a further three sub-rules. The sorption-desorption processes are temperature dependent and will be drastically slowed in frozen soils. The ideas of Brusseau (2019), Nguyen et al. (2020), Gassmann et al. (2020), and Gassmann et al. 2020) suggest that cyclical reduction-oxidation processes which dissolve and recrystallize amorphous iron oxides could play a role in the entrapment and release of PFAS at air-water interfaces. Since not all water movement in soils is vertical, the lateral component of PFAS movement must be considered. In a reduced soil, PFAS, ferrous iron, and water will flow laterally downslope. Once an oxidized condition is encountered the ferrous iron will oxidize and demobilize. The PFAS may be entrapped in the oxides. The water table fluctuation, temperature, and slope subrule considers flow of water, ferrous iron, and PFAS laterally through soil. The temperature of the system is known to affect the rates of chemical reactions and presumably the rates of sorption and desorption which in turn affects attenuation. Not mentioned here, although it perhaps should be, is the effect of frozen soil on the attenuation of PFAS. Soils in areas where the mean annual air temperature is less than 10 degrees C are likely to be frozen to some depth for some time during the year. These dynamics are yet to be studied. For the current model, it is considered that higher temperature will enhance attenuation of PFAS because of the temperature effect on biological and chemical systems. Any appreciable slope on the landscape is assumed to drive lateral movement under saturated conditions. In soils having slope less than 5 percent it is assumed that PFAS will be attenuated in place. On steeper slopes, it is postulated that less attenuation will occur as the soil water moves downslope.

Relationships between water table fluctuations, oxidation-reduction processes, iron oxide chemistry, and PFAS attenuation have not yet been thoroughly explored. A net gain in attenuation is hypothesized here because of the dissolution and precipitation of iron is thought to form structures where the PFAS anions may be held. While other soil features may affect the ability of a soil to hold PFAS, currently the thickness of soil that is affected by the rising and falling of the zone of saturation is considered here. Since the air-water interface seems to be important for this process, this sub-rule examines the distance between the top of the shallowest water depth and the top of the deepest water depth or 200cm. This sub-rule has no effect if no water table is present. The occurrence of lateral water movement is theorized to allow less attenuation because the PFAS is moving with water and any reduced iron, so less time is available for precipitation of the iron species. Note that if a fluctuating water table does not exist, this sub-rule does not contribute to PFAS attenuation.

In this iteration of the model, the effects of each sub-rule are summed to obtain the overall relative attenuation capacity of a soil.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils will attenuate PFAS by all of the soil features that affect this process. "High attenuation" indicates that the soil has features that are very favorable for immobilizing PFAS. A sampling plan should concentrate on near-surface layers. "Moderately high attenuation" suggests that while the bulk of PFAS will be near the soil surface, some may be moving downward. "Moderate attenuation" suggests that downward movement is to be expected. "Moderately low attenuation" indicates that the PFAS may have moved below the soil surface and be heading toward the groundwater or moving laterally to a surface outlet. "Low attenuation" indicates that soil features are not conducive to stopping or slowing PFAS movement and that subsurface or surface water contamination is likely.

Numerical ratings indicate the degree of attenuation. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the least predicted ability to hold PFAS (0.00) and the point at which the soil features are predicted to hold PFAS tightly (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Brusseau, Mark L. 2019. The influence of molecular structure on the adsorption of PFAS to fluid-fluid interfaces: Using QSPR to predict interfacial adsorption coefficients. Water Research 152 (2019) 148e158.

Campos-Pereira, Hugo, Dan B. Kleja, Carin Sjostedt, Lutz Ahrens, Wantana Klysubun, and Jon Petter. Gustafsson. 2020. The Adsorption of Per- and Polyfluoroalkyl Substances (PFASs) onto Ferrihydrite Is Governed by Surface Charge. Environmental Science & Technology. 54 (24), 15722-15730. DOI: 10.1021/acs.est.0c01646.

Evich, M. G. et al. 2022. Per- and polyfluoroalkyl substances in the environment. Science 375, eabg9065 (2022). DOI: 10.1126/science.abg9065.

EPA Technical Factsheet. https://19january2021snapshot.epa.gov/sites/static/files/2017-12/documents/ffrrofactsheet_contaminants_pfos_pfoa_11-20-17_508_0.pdf.

Gassmann, Matthias, Eva Weidemann, Thorsten Stahl. 2020. Combined leaching and plant uptake simulations of PFOA and PFOS under field conditions. Environmental Science and Pollution Research (2021) 28:2097, 2107. https://doi.org/10.1007/s11356-020-10594-6.

Li, Yasong, Danielle P. Oliver, Rai S. Kookana. 2018. A critical analysis of published data to discern the role of soil and sediment properties in determining sorption of per and polyfluoroalkyl substances (PFASs). https://doi.org/10.1016/j.scitotenv.2018.01.167.

National Cooperative Soil Survey PFAS Factsheet. https://www.whidbeycd.org/uploads/1/1/6/8/11683986/pfafactshee.pdf.

Nguyen, Thi Minh Hong, Jennifer Braunig, Kristie Thompson, Jack Thompson, Shervin Kabiri, Divina A. Navarro, Rai S. Kookana, Charles Grimison, Craig M. Barnes, Christopher P. Higgins, Michael J. McLaughlin, and Jochen F. Mueller. 2020. Influences of Chemical Properties, Soil Properties, and Solution pH on Soil, Water Partitioning Coefficients of Per- and Polyfluoroalkyl Substances (PFASs). Environmental Science & Technology 2020 54 (24), 15883-15892. DOI: 10.1021/acs.est.0c05705.

Uwayezu, Jean-Noel, Leo W.Y. Yeung, Mattias Backstrom. 2019. Sorption of PFOS isomers on goethite as a function of pH, dissolved organic matter (humic and fulvic acid) and sulfate. Chemosphere 233 (2019) 896e904. https://doi.org/10.1016/j.chemosphere.2019.05.252.

PFAS

PFAS Movement in Soils

Background

Per- and Polyfluoroalkyl substances (PFAS) are a large group of man-made substances. According to the National Cooperative Soil Survey PFAS Factsheet, they were used in wide variety of products such as waterproofing sealants, food packaging, non-stick cookware, and fire-fighting foams. These compounds are not readily broken down in the environment and because of this, they are very persistent. In their review of the PFAS literature, Evich et al. (2022) describe PFAS chemicals, their movement in the environment, uptake by plants and animals, and their fate. Briefly, PFAS molecules are large anions (negatively charged particles) that can move through soil and into ground water, plants, animals, and people. Because they can also move in the atmosphere, PFAS chemicals can be found everywhere in low concentrations. Land application of municipal sewage sludge and irrigation water containing PFAS are two ways these chemicals have been introduced in large concentrations on farms. Evidence of bioaccumulation of PFAS in human tissues is associated with negative health impacts.

PFAS Movement on and Through the Landscape

The focus of this work is to create a model to predict where PFAS will go when it is introduced at the soil surface. PFAS molecules are generally large anions that interact with soil constituents. These compounds are generally expected to move in solution with soil water or tied to soil particles in the case of erosion. Soil and landscape features influence the movement of water and so should also have some bearing on the direction of PFAS translocation. The rate of movement is the subject of another model. The model described here consists of rules having one or more levels of sub-rules and attempts to predict the fate of PFAS based on soil and landscape features.

Four pathways are proposed: 1. Direct runoff, related to slope and infiltration, with rapid transport to surface waters by overland flow. 2. Subsurface runoff or subsurface stormwater flow to surface water, with sorption/desorption of solutes in transit. 3. Rapid infiltration to groundwater, with little sorption or desorption in transit. 4. Slow movement to groundwater.

It is suggested that programs of soil sampling for PFAS should consider where the chemical might be expected to be found. Variables such as rainfall and irrigation also need to be accounted for in estimating the pathway of PFAS through the landscape.

Discussion

The "Movement Classes" model is a "class style" interpretation where the fuzzy numbers produced by the sub-rules are manipulated to fit into certain classes as is spelled out by the rating classes. These are shown in the table below. For a class style interpretation to display on Web Soil Survey, a distinct "Not rated" class, set to 0, is needed instead of "null not rated" when nulls are encountered.

The classes are mutually exclusive, but it will be seen that some soil components will have a dominant transmission style and a secondary style.

Rating class names and boundaries: Rating Class Name Rating Class Rating Class Lower Boundary Upper Boundary ------------------------------------------------------------------ Transmission to groundwater 0.751 1.000 Overland flow to surface water 0.502 0.750 Subsurface flow to surface water 0.252 0.501 Slow transmission to groundwater 0.001 0.251 Not rated 0

Literature

Li, Yasong, Danielle P. Oliver, Rai S. Kookana. 2018. A critical analysis of published data to discern the role of soil and sediment properties in determining sorption of per and polyfluoroalkyl substances (PFASs). https://doi.org/10.1016/j.scitotenv.2018.01.167.

Evich, M. G. et al. 2022. Per- and polyfluoroalkyl substances in the environment. Science 375, eabg9065 (2022). DOI: 10.1126/science.abg9065

EPA Technical Factsheet. https://19january2021snapshot.epa.gov/sites/static/files/2017-12/documents/ffrrofactsheet_contaminants_pfos_pfoa_11-20-17_508_0.pdf

National Cooperative Soil Survey PFAS Factsheet. https://www.whidbeycd.org/uploads/1/1/6/8/11683986/pfafactshee.pdf

Phosphorus Index (TX) interpretation rates each soil's limitations for the application and sequestration of phosphorus or phosphorus mineralization. The interpretation assesses the soil's potential to maintain and sequester phosphorus and phosphorus mineralization byproducts on site and prevent surface water pollution. Soil properties and qualities considered are those that affect soil absorption such as soil depth, runoff potential, and surface water features. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and phosphorus sequestration can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or application. Fair performance and moderate phosphorus sequestration can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive application. Poor performance and high expense can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one shown for the map unit. The percent composition of each component in a particular map unit is given to help the user better understand the extent to which the rating applies to the map unit. Other components with different ratings may occur in each map unit. The ratings for all components, regardless the aggregated rating of the map unit, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

URB/REC - Urban and Recreational Land Uses

Picnic areas are natural or landscaped tracts used primarily for preparing meals and eating outdoors. These areas are subject to heavy foot traffic. Most vehicular traffic is confined to access roads and parking areas.

The ratings are based on the soil properties that affect the ease of developing picnic areas and that influence trafficability and the growth of vegetation after development. Slope and stoniness are the main concerns affecting the development of picnic areas. For good trafficability, the surface of picnic areas should absorb rainfall readily, remain firm under heavy foot traffic, and not be dusty when dry. The soil properties that influence trafficability are texture of the surface layer, depth to a water table, ponding, flooding, saturated hydraulic conductivity (Ksat), and large stones. The soil properties that affect the growth of plants are depth to bedrock or a cemented pan, saturated hydraulic conductivity (Ksat), and toxic substances in the soil.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

URB/REC - Urban and Recreational Land Uses

Playgrounds are areas used intensively for games, such as baseball and football, and similar activities. Playgrounds require soils that are nearly level, are free of stones, and can withstand intensive foot traffic.

The ratings are based on the soil properties that affect the ease of developing playgrounds and that influence trafficability and the growth of vegetation after development. Slope and stoniness are the main concerns affecting the development of playgrounds. For good trafficability, the surface of the playgrounds should absorb rainfall readily, remain firm under heavy foot traffic, and not be dusty when dry. The soil properties that influence trafficability are texture of the surface layer, depth to a water table, ponding, flooding, saturated hydraulic conductivity (Ksat), and large stones. The soil properties that affect the growth of plants are depth to bedrock or a cemented pan, saturated hydraulic conductivity (Ksat), and toxic substances in the soil.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Pond reservoir areas hold water behind a dam or embankment. Soils best suited to this use have low seepage potential in the upper 60 inches. The seepage potential is determined by the saturated hydraulic conductivity (Ksat) of the soil and the depth to fractured bedrock or other permeable material. Excessive slope can affect the storage capacity of the reservoir area. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

TBD The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

TBD The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Description - ENG-Catastrophic Mortality, Poultry Disposal, Compost (PA)

Composting catastrophic mortalities is a method of disposing of large quantities of dead birds as a result of a catastrophic or disease related incident. Composting in this scenario is a managed process where decomposition converts carcasses into a stable organic material. Additionally this process can deactivate harmful pathogens and viruses that may be present. The carcasses are mixed with a carbonaceous material, like mulch or wood chips at a recommended rate to achieve the optimum carbon to nitrogen (C:N) ratio. The mixture is formed into a windrow and placed on a thick base (12 inches or more) of similar uncompact carbonaceous material. Once constructed to its designed size, a final cover of carbonaceous material is placed over the windrow as a cap ensuring all parts of the carcasses are covered.

This report evaluates a site's characteristics in order to provide a reliable disposal location and provides ratings regarding the protection of ground and surface water as well as equipment maneuverability. While general assumptions of the suitability of a site are provided, an on-site evaluation is required to ensure adequate design and performance of the disposal site. This method utilizes a site's undisturbed surficial and soil characteristics. Ratings do not consider present land use.

Ratings are based on properties and qualities to the depth of 79 inches (200cm) or to bedrock if shallower, the depth normally observed when developing soil surveys. By utilizing the undisturbed soil surface and employing the minimum windrow base thickness, sites that rate less limiting than "severe" are expected to perform with minimal concern for negative effects.

Properties that influence the risk of pollution, trafficability, and windrow stability are the major considerations. Pollution is a hazard on soils that are subject to flooding, have high saturated hydraulic conductivity or are shallow to bedrock or water table. Slope affects windrow construction and stability, maneuverability of equipment and vehicles, and the control of surface water around the windrows. Surface stoniness, depth to water table, and rock outcrops affect trafficability and windrow design and location.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which soils are limited by all of the soil features that affect these uses. "Slight" limitation indicates that the soil has features that are desirable for the specified use. Minor considerations may exist. Very good performance can be expected. "Moderate" limitation indicates that the soil has features that are less favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Good performance can be expected. "Severe" limitation indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Seasonal variations may impact specific soil properties like flooding and depth to seasonal high water table. Consideration should be given to such circumstances when applying this interpretation to ensure optimal performance. An additional report that can help identify the seasonal variation of soil water is the Water Features report. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.00 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The soil components listed for each map unit in the generated report in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by an aggregation method. An aggregated rating class is shown for each map unit. The percent of each component in a map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Alberta Canada. 2005. Alberta Agricultural Food and Rural Development. Manure Composting Manual.

Britton, Jim. F-8216. Catastrophic Poultry Mortality Loss: Handling and Disposal Alternatives.

Flory, Gary A., Bendfeldt, Eric S., Peer, Robert W., Zirkle, C., Malone, George W. Sept. 15, 2006. Guidelines for In-House Composting Poultry Mortality as a Rapid Response to Avian Influenza.

Ithaca, NY. 1992. Northeast Regional Agricultural Engineering Service. On-Farm Composting Handbook.

e

Lined retention systems are stormwater management practices that are placed 3 to 5 feet in the ground, depending on the application. An impervious liner, made of rubber or clay, is used to retain water and thus to maintain hydrophytic vegetation. These systems are meant to be used where the hydrology will not allow other systems, but the slope and bedrock depth are favorable. These systems include retention basins and intermittent wetlands. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated by an area, such as a parking lot, from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. Water should not be at the surface continuously, but a water table within the depth of the system is needed to allow the growth of hydrophytic vegetation. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Some land shaping may be needed to allow stormwater runoff to accumulate in the system. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water

Soils that are underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system may adversely affect water quality and public health. In these soils the lined retention system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one listed for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit.

The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Unlined retention systems are stormwater management practices that are placed 3 to 5 feet in the ground, depending on the application. These systems include retention basins and intermittent wetlands. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated by an area, such as a parking lot, from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. Water should not be at the surface continuously, but a water table within the depth of the system is needed to allow the growth of hydrophytic vegetation.. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water.

Soils underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system may adversely affect water quality and public health. In these soils the unlined retention system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure.. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one listed for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit.

The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Shallow infiltration systems are stormwater management practices that are placed 1 to 3 feet in the ground, depending on the application. These systems include pervious pavement, buffer strips, filter strips, and vegetated swales. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated by an area, such as a parking lot, from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. There should be little or no ponding at the surface. The water should infiltrate into the surrounding soil in 24 to 48 hours. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water.

Soils underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system may adversely affect water quality and public health. In these soils the shallow infiltration system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified infiltration system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one listed for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit.

The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Slow rate treatment of wastewater is a process in which wastewater is applied to land at a rate normally between 0.5 inch and 4.0 inches per week. The application rate commonly exceeds the rate needed for irrigation of cropland. The applied wastewater is treated as it moves through the soil. Much of the treated water may percolate to the ground water, and some enters the atmosphere through evapotranspiration. The applied water generally is not allowed to run off the surface. Waterlogging is prevented either through control of the application rate or through the use of tile drains, or both. Soil properties are important considerations in areas where soils are used as sites for the treatment and disposal of organic waste and wastewater. Selection of soils with properties that favor waste management can help to prevent environmental damage. Municipal wastewater is the waste stream from a municipality. It contains domestic waste and may contain industrial waste. It may have received primary or secondary treatment. It is rarely untreated sewage. Food-processing wastewater results from the preparation of fruits, vegetables, milk, cheese, and meats for public consumption. In places it is high in content of sodium and chloride. The effluent in lagoons and storage ponds is from facilities used to treat or store food-processing wastewater or domestic or animal waste. Domestic and food-processing wastewater is very dilute, and the effluent from the facilities that treat or store it commonly is very low in content of carbonaceous and nitrogenous material; the content of nitrogen commonly ranges from 10 to 30 milligrams per liter. The wastewater from animal waste treatment lagoons or storage ponds, however, has much higher concentrations of these materials, mainly because the manure has not been diluted as much as the domestic waste. The content of nitrogen in this wastewater generally ranges from 50 to 2,000 milligrams per liter. When wastewater is applied, checks should be made to ensure that nitrogen, heavy metals, and salts are not added in excessive amounts. The ratings are based on the soil properties that affect absorption, plant growth, microbial activity, erodibility, and the application of waste. The properties that affect absorption include the sodium adsorption ratio, depth to a water table, ponding, available water capacity, saturated hydraulic conductivity (Ksat), depth to bedrock or a cemented pan, reaction, the cation-exchange capacity, and slope. Reaction, the sodium adsorption ratio, salinity, and bulk density affect plant growth and microbial activity. The wind erodibility group, soil erosion factor K, and slope are considered in estimating the likelihood of wind erosion or water erosion. Stones, cobbles, a water table, ponding, and flooding can hinder the application of waste. Permanently frozen soils are unsuitable for waste treatment. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect agricultural waste management. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings for Subsurface Water Management, Outflow Quality are based on the soil properties that affect the capacity of the soil to convey surface and subsurface water and on the properties that affect water quality. The properties that affect the conveyance and water quality include salinity, sodicity, soil reaction, soil taxonomic great group placement, gypsum content, shrink-swell potential, soil saturation, and surface erosion. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor water quality can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating.

A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings for Subsurface Water Management, System Installation are based on the soil properties that affect the capacity of the soil to be drained and on the properties that affect excavation and construction costs. The properties that affect the subsurface system installation include depth to a water table, ponding, flooding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, slope, clay content, excavation stability, and the amount and size of rock fragments. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating.

A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings for Subsurface Water Management, System Performance are based on the soil properties that affect the capacity of the soil to be drained. The properties that affect the subsurface system performance include depth to a water table, salinity, flooding, sodicity, sand content, soil reaction, hydraulic conductivity, soil density, gypsum content, and subsidence. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating.

A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings for Surface Water Management, System are based on the soil properties that affect the capacity of the soil to convey surface water across the landscape. Factors affecting the system installation and performance are considered. Water conveyances include graded ditches, grassed waterways, terraces, and diversions. The ratings are for soils in their natural condition and do not consider present land use. The properties that affect the surface system performance include depth to bedrock, saturated hydraulic conductivity, depth to cemented pan, slope, flooding, ponding, large stone content, sodicity, surface water erosion, and gypsum content. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating.

A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Unlined retention systems are stormwater management practices that are placed 3 to 5 feet in the ground, depending on the application. These systems include retention basins and intermittent wetlands. They slow the movement of stormwater to surface waters and also filter a significant portion of pollutants from the stormwater. The fundamental function of these systems is to hold the runoff generated by an area, such as a parking lot, from the first 1 inch of rainfall during a 24-hour storm preceded by 48 hours of no measurable precipitation. Water should not be at the surface continuously, but a water table within the depth of the system is needed to allow the growth of hydrophytic vegetation.. Only that part of the soil between depths of 24 and 80 inches is evaluated.

The ratings are based on the soil properties that affect infiltration of the stormwater, construction and maintenance of the system, and public safety and health. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect the transmission of rainwater. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the water in downslope areas. Some slopes may become unstable and move upon addition of water.

Soils underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the bottom of the system may adversely affect water quality and public health. In these soils the unlined retention system may not adequately filter the stormwater, particularly if the adsorptive capacity of the soil below the system is low. As a result, the ground water may become contaminated. In areas underlain by limestone, solution channels and subsequent subsidence may damage adjacent infrastructure.. Also, areas underlain by limestone may be subject to ground-water contamination.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified system. "Not limited" indicates that the soil has features that are very favorable for the specified system. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified system. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified system. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified system (1.00) and the point at which the soil feature is not a limitation (0.00).

The accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer lists the map unit components. These components are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as the one listed for the map unit. The percent composition of each component in a particular map unit is shown to help the user better understand the percentage of each map unit that has the rating indicated. Other components with different ratings may occur in each map unit.

The complete ratings list for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is designed to predict the inherent soil erosion hazard, based on the criteria described in a revision of the U.S. Forest Service Inherent Erosion Hazard Rating Handbook and the Soil - Hydrologic Reconnaissance of the Krassel Ranger District, Payette National Forest. The complete citations for the source documents are at the end of this description (1, 2).

The interpretation ratings are based on bare soil conditions and reflect the ability of the soil to take in water, resistance of the soil surface to dispersion under the impact of rainfall and surface water movement, effect of rock fragments that reduce surface detachment, and effect of topography.

The following factors are used to determine the inherent erosion hazard rating:

1. Detachability Index (DI) - based on the ability of soil surface horizon aggregates to resist detachment or dispersion after wetting. The index is based on the aggregate stability, which is predicted by the clay content, organic matter content, and sodium adsorption ratio of the upper 6 inches (15 cm) of the first mineral horizon, below any organic forest litter surface horizons (3). Numerical ratings range from 0.01 to 1.00. The higher the numerical rating, the higher is the detachability index.

2. Profile Permeability Rating (PPR) - based on the permeability (saturated hydraulic conductivity) in inches per hour) of the surface mineral horizon and reduction and depth to reduction in permeability rates in horizons deeper in the soil profile. The slower the surface horizon permeability and the larger the reduction in permeability rates in deeper horizons, the higher is the profile permeability rating. Numerical ratings range from 0.01 to 1.00. The higher the numerical rating, the higher is the profile permeability rating.

3. Rock fragment content (RF_content) - based on the weighted average rock fragment content by volume in the upper 6 inches (15 cm) of the first mineral horizon, below any organic forest litter surface horizons. Rock fragment content is converted from percent to a decimal format (i.e. 30 percent rock fragments = 0.30). Numerical ratings range from 0.00 to 1.00.

4. Slope gradient - percent slope, converted to a decimal format (i.e. 45 percent slope = 0.45)

The first step in the Inherent Erosion Hazard (IEH) rating determination is to calculate a Soil Erodibility Index (SEI) with the equation below:

SEI = DI * (1.00 - (RF_content) / 100)) * PPR Where DI = Detachability Index, RF_content = Rock fragment content (decimal format), and PPR = Profile Permeability Rating.

The final step is the equation below:

IEH = SEI + slope gradient (decimal format)

Inherent Erosion Numerical Rating and Class:

Low: Less than or equal to 0.19 Moderately low: 0.20- 0.39 Moderate: 0.40 - 0.58 Moderately high: 0.59 - 0.79 High: Greater than or equal to 0.800

Rating Class Definitions:

High - Unprotected bare soil will erode sufficiently to severely and permanently damage the production capacity of the soil or will yield excessively high volumes of sediment.

Moderately high - Unprotected bare soil will erode sufficiently to severely damage productive capacity or will yield high volumes of sediment.

Moderate - Sufficiently resistant to erosion to permit limited and temporary exposure of bare soil during development or use.

Moderately low - Sufficiently resistant to erosion to permit exposure of bare soil under minimal precautionary restrictions.

Low - No appreciable hazard of erosion.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. An onsite investigation may be needed to validate the interpretation rating classes and confirm the identity of the soil on a given site.

References:

(1) Arnold, John F. 1988. Proposals for Making Natural Sedimentation Rate and Geologic Erosion Factor Estimates for the Boise and Payette National Forests and Land Type Associations and Zone Maps for the Payette National Forest.

(2) - Forest Service. 1970. Soil-Hydrologic Reconnaissance of the Krassel Ranger District, Payette National Forest.

(3) -ARS. 1966. Aggregate stability of soils from western United States and Canada. Tech. Bull. No. 1355. Agricultural Research Service, United States Department of Agriculture in cooperation with Colorado Agricultural Experiment Station. U.S. Government Printing Office. Washington, D.C.

This soil interpretation is intended to provide ratings based on the dominant soil characteristics that influence the suitability of the soil for excavation, maintenance, and preservation of burrows by gopher tortoises (Gopherus polyphemus). The information allows the user to identify areas of potentially suitable habitat area prior to the application of conservation practices. The ratings are for the soils in their natural condition and do not consider present land use, existing vegetation, water sources, and the presence or absence of wildlife in the area. The presence or absence of a species is determined at the local level and by many factors including soil characteristics. The gopher tortoise (Gopherus polyphemus) is a burrowing reptile that inhabits open pine forests throughout the southeastern United States. Historically, typical gopher tortoise habitat consisted of open, frequently burned longleaf pine or longleaf pine/scrub oak uplands and flatwoods on moderately well drained to xeric soils. The burrows of a gopher tortoise are the habitat and center of normal feeding, breeding, and sheltering activity. Gopher tortoises excavate and use more than one burrow for shelter beneath the ground surface. Burrows, which may extend for more than 30 feet, provide shelter from canid predators, winter cold and summer heat.

The soil criteria that are taken into account in this soil interpretation are those that have been determined to have the most effect on burrow excavation, maintenance, and preservation. These include the soil texture, percent coarse fragments, depth to a restrictive layer or layer with greater than or equal to 35% clay, ponding or flooding frequency, slope, and depth to seasonal high water table. Each soil criteria is assigned a numerical rating between 0 and 1. In this rating, 1 represents more suitable soil characteristics, and 0 represents less suitable soil characteristics. Each criterion is calculated separately and the lowest rating is reported as the overall soil suitability rating, representing the most limiting factor in the soil's suitability for gopher tortoise burrows. Rating classes have been defined as follows: Highly suited (numerical rating 0.95-1): These soils have no restrictions for use and are favorable for burrowing by gopher tortoise. Colonization and population densities may be above average if other habitat factors are not limiting. Moderately suited (numerical rating 0.5-0.95): These soils are suitable and somewhat favorable for burrowing by gopher tortoise. Some restrictive features may limit the use of the site to a minor extent. Colonization and population densities may be average to above for the area if the other habitat requirements are met. Less suited (numerical rating 0.05-0.5): These soils have characteristics that may limit establishment, maintenance, or use of the site by gopher tortoise. Colonization and population densities may be below average or restricted in the area due to the limiting factors even though all of the other species habitat requirements are met. Unsuitable (numerical rating 0-0.05): These soils have characteristics that may limit establishment, maintenance, or use of the site by gopher tortoise. Areas of included soils with better drainage may provide suitable soil properties in some locations. Not Rated: Miscellaneous areas are given a not rated status.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen, which is displayed on the report. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the Selected Soil Interpretations report with this interpretation included from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site. Citations: U.S. Fish and Wildlife Service and Natural Resources Conservation Service. 2012. Gopher Tortoise (Gopherus polyphemus) Soil Classifications for the Federally Listed Range using the National Soil Information System Database, Version 1.

Bivouac areas are used intensively as field operation centers for military activity. They commonly require site preparation, such as shaping and leveling in areas used for tents and in parking areas, stabilizing roads and intensively used areas, and installing sanitary facilities and utility lines. Bivouac areas are subject to heavy foot traffic and some vehicular traffic.

This interpretation identifies those soil properties that influence the ease of developing bivouac areas and the performance of the areas after development. Soil properties that influence trafficability and promote the growth of vegetation after heavy use also are important. The limitations are less restrictive on sites for tents or remote camps.

Slope, stoniness, and depth to bedrock or a cemented pan are the main concerns in developing bivouac areas. For good trafficability, the surface of the bivouac area should absorb rainfall readily, should remain firm under heavy foot traffic, and should not be dusty when dry. Soil properties that influence trafficability are texture of the surface layer, wetness, saturated hydraulic conductivity (Ksat), and large stones. The limitations of low Ksat and a clayey surface layer are not so severe in dry regions of the country as in other regions; however, silty soils may be more of a problem in the dry regions because they are dusty. Soil properties that influence the growth of plants are depth to bedrock or a cemented pan, saturated hydraulic conductivity (Ksat), and the presence of toxic materials. Soils that are subject to flooding are particularly hazardous as bivouac areas because of the danger to life and property.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect bivouac areas. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

These excavations are trenches or holes dug in the soil to a maximum depth of 5 or 6 feet. They are used for troop and weapon protection and support bases. The excavations are most commonly made by trenching machines or backhoes.

Ratings are based on the soil properties that influence the ease of digging, the resistance to sloughing, and weapon readiness. Depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the content of large stones influence the ease of digging, filling, and compacting. Depth to the seasonal high water table and flooding may restrict the period when excavations can be made and can affect weapon readiness. Slope influences the ease of using machinery. Soil texture and depth to the water table influence the resistance to sloughing.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these excavations. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

These excavations are trenches or holes dug in the soil to a maximum depth of 2 or 3 feet. They are used for troop protection. The excavations are most commonly made by trenching tools and shovels.

Ratings are based on the soil properties that influence the ease of digging, the resistance to sloughing, and position readiness. Depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the content of large stones influence the ease of digging, filling, and compacting. Depth to the seasonal high water table and flooding may restrict the period when excavations can be made and can affect position readiness.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these excavations. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

These excavations are trenches or holes dug in the soil to a maximum depth of 5 or 6 feet. They are used for troop, vehicle, and weapon protection and support bases. The excavations are most commonly made by trenching machines or backhoes.

Ratings are based on the soil properties that influence the ease of digging, the resistance to sloughing, and weapon readiness. Depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the content of large stones influence the ease of digging, filling, and compacting. Depth to the seasonal high water table and flooding may restrict the period when excavations can be made and can affect weapon readiness. Slope influences the ease of using machinery. Soil texture and depth to the water table influence the resistance to sloughing.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these excavations. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Helicopter landing zones are areas that are developed for landing helicopters that transport troops and supplies.

Ratings are based on the soil properties that influence construction, maintenance, and readiness of the landing zones. A dusty surface layer, slope, and the content of large stones influence the development and functionality of the landing zone. Flooding or ponding may restrict the period when the landing zone can be used.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect helicopter landing zones. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 1 vehicles are lightweight and have low contact pressure (less than 2.0 pounds per square inch). For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for one vehicle pass. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 1 vehicles are lightweight and have low contact pressure (less than 2.0 pounds per square inch). For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a maximum of 50 vehicle passes in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 1 vehicles are lightweight and have low contact pressure (less than 2.0 pounds per square inch). For this interpretation, trafficability is the capacity of the soil to support these vehicles during dry periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a minimum number of vehicle passes (one) or a maximum of 50 vehicles in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 2 vehicles are engineer and high-speed tractors with comparatively wide tracks and low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for one vehicle pass. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 2 vehicles are engineer and high-speed tractors with comparatively wide tracks and low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a maximum of 50 vehicle passes in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 2 vehicles are engineer and high-speed tractors with comparatively wide tracks and low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during dry periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a minimum number of vehicle passes (one) or a maximum of 50 vehicles in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 3 vehicles are tractors with average contact pressures, tanks with comparatively low contact pressures, and some trailed vehicles with very low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use

Trafficability performance was estimated for one vehicle pass. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 3 vehicles are tractors with average contact pressures, tanks with comparatively low contact pressures, and some trailed vehicles with very low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for 50 vehicle passes in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 3 vehicles are tractors with average contact pressures, tanks with comparatively low contact pressures, and some trailed vehicles with very low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during dry periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use

Trafficability performance was estimated for a minimum number of vehicle passes (one) or a maximum of 50 vehicles in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

Military category type 4 vehicles are most medium tanks, tractors with high contact pressures, and all-wheel-drive trucks and trailed vehicles with low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for one vehicle pass. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 4 vehicles are most medium tanks, tractors with high contact pressures, and all-wheel-drive trucks and trailed vehicles with low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for 50 vehicle passes in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 4 vehicles are most medium tanks, tractors with high contact pressures, and all-wheel-drive trucks and trailed vehicles with low contact pressures. For this interpretation, trafficability is the capacity of the soil to support these vehicles during dry periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a minimum number of vehicle passes (one) or a maximum of 50 vehicles in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 5 vehicles are most all-wheel-drive trucks, a great number of trailed vehicles, and heavy tanks. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for one vehicle pass. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 5 vehicles are most all-wheel-drive trucks, a great number of trailed vehicles, and heavy tanks. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for 50 vehicle passes in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 5 vehicles are most all-wheel-drive trucks, a great number of trailed vehicles, and heavy tanks. For this interpretation, trafficability is the capacity of the soil to support these vehicles during dry periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a minimum number of vehicle passes (one) or a maximum of 50 vehicles in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 6 vehicles are a great number of all-wheel-drive and rear-wheel-drive trucks and trailed vehicles intended primarily for highway use. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for one vehicle pass. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 6 vehicles are a great number of all-wheel-drive and rear-wheel-drive trucks and trailed vehicles intended primarily for highway use. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for 50 vehicle passes in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 6 vehicles are a great number of all-wheel-drive and rear-wheel-drive trucks and trailed vehicles intended primarily for highway use. For this interpretation, trafficability is the capacity of the soil to support these vehicles during dry periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a minimum number of vehicle passes (one) or a maximum of 50 vehicles in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 7 vehicles are rear-wheel-drive and other vehicles that generally are not expected to operate off road, especially on wet soils. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for one vehicle pass. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 7 vehicles are rear-wheel-drive and other vehicles that generally are not expected to operate off road, especially on wet soils. For this interpretation, trafficability is the capacity of the soil to support these vehicles during wet periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils when wet is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for 50 vehicle passes in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Military category type 7 vehicles are rear-wheel-drive and other vehicles that generally are not expected to operate off road, especially on wet soils. For this interpretation, trafficability is the capacity of the soil to support these vehicles during dry periods. Trafficability estimates can be made from terrain data, such as topography data, and from data about soil and weather conditions. Military trafficability interpretations are based on procedures and criteria described in the Army Field Manual 5-430-00-1, chapter 7, and are conservative estimates for use in operations planning. Commanders and engineers must be cautious because the interpreted results can vary greatly.

Assessing the trafficability of fine grained soils (silts and clays) and sands that contain enough fine grained material to behave like fine grained soils is more difficult than assessing the trafficability of coarse grained soils (clean sands). Soil-vehicle interactions involving soil strength, slipperiness, stickiness, large stones on the surface, and slope are the basis for trafficability interpretations.

The information presented in this interpretation is limited to problems associated with soils. It does not include problems associated with natural or manmade obstacles (such as forests or ditches) or with vehicle characteristics (such as the maximum tilt or side angle at which a vehicle can climb without power stall or overturning). The interpretation is developed for temperate and tropical climates and for soils that have been subject to freeze-thaw cycles if they are not frozen at the time of vehicle use.

Trafficability performance was estimated for a minimum number of vehicle passes (one) or a maximum of 50 vehicles in the same ruts. Slope, stoniness, depth to bedrock or a cemented pan, flooding, ponding, and the Unified soil classification are the main soil properties used in determining vehicular trafficability. For good trafficability, the surface of the soil should absorb rainfall readily, should remain firm under repeated traffic, and should not be dusty when dry. Soil properties that influence soil strength, slickness, and stickiness are the Unified soil classification and its relationship to soil moisture conditions and surface ponding, flooding, and stoniness.

The ratings are both verbal and numerical. Rating classes of "excellent," "good," "fair," and "poor" indicate the extent to which the soils are suitable for military vehicle traffic. "Excellent" indicates that the soil has no characteristics that limit trafficability and that very low maintenance can be expected. "Good" indicates that the soil may have characteristics that limit trafficability but are favorable for use. Good operational performance and low maintenance can be expected. The limitations can be overcome or minimized by special planning, design, or management. "Fair" indicates that the soil has characteristics that limit trafficability and are moderately favorable for use. The limitations can be overcome or minimized by special planning, design, or management. Fair performance, moderate maintenance, and soil degradation can be expected. "Poor" indicates that the soil has characteristics that severely limit trafficability and one or more features that are unfavorable for use. Generally, the limitations cannot be overcome without major soil reclamation, special design, or special management. Poor performance, high maintenance, and soil degradation can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (0.01) and the point at which the soil feature is not a limitation (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Daily cover for landfill is the soil material that is used to cover compacted solid waste in a sanitary landfill. The soil material is obtained offsite, transported to the landfill, and spread over the waste. The ratings also apply to the final cover for a landfill. They are based on the soil properties that affect workability, the ease of digging, and the ease of moving and spreading the material over the refuse daily during wet and dry periods. These properties include soil texture, depth to a water table, ponding, rock fragments, slope, depth to bedrock or a cemented pan, reaction, and content of salts, sodium, or lime.

Loamy or silty soils that are free of large stones and excess gravel are the best cover for a landfill. Clayey soils may be sticky and difficult to spread; sandy soils are subject to wind erosion.

Slope affects the ease of excavation and of moving the cover material. Also, it can influence runoff, erosion, and reclamation of the borrow area.

The soil material used as the final cover for a landfill should be suitable for plants. It should not have excess sodium, salts, or lime and should not be too acid. After soil material has been removed, the soil material remaining in the borrow area must be thick enough over bedrock, a cemented pan, or the water table to permit revegetation. Some damage to the borrow area is expected, however, and plant growth may not be optimum.

This information is intended for land use planning, for evaluating land use alternatives, and for planning site investigations prior to design and construction. The information, however, has limitations. For example, estimates and other data generally apply only to that part of the soil between the surface and a depth of 5 to 7 feet. Because of the map scale, small areas of different soils may be included within the mapped areas of a specific soil.

The information is not site specific and does not eliminate the need for onsite investigation of the soils or for testing and analysis by personnel experienced in the design and construction of engineering works.

Government ordinances and regulations that restrict certain land uses or impose specific design criteria were not considered in preparing the ratings. Local ordinances and regulations should be considered in planning, in site selection, and in design.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings in the table indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Dwellings are single-family houses of three stories or less. For dwellings with basements, the foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of about 7 feet.

The ratings for dwellings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs. The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility (shrink-swell potential), and compressibility. Compressibility is inferred from the Unified classification of the soil. The properties that affect the ease and amount of excavation include depth to a water table, ponding, flooding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Dwellings are single-family houses of three stories or less. For dwellings without basements, the foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of 2 feet or at the depth of maximum frost penetration, whichever is deeper.

The ratings for dwellings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs. The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility (shrink-swell potential), and compressibility. Compressibility is inferred from the Unified classification of the soil. The properties that affect the ease and amount of excavation include depth to a water table, ponding, flooding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Gravel consists of natural aggregates (2 to 75 millimeters in diameter) suitable for commercial use with a minimum of processing. It is used in many kinds of construction. Specifications for each use vary widely. Only the probability of finding material in suitable quantity is evaluated. The suitability of the material for specific purposes is not evaluated, nor are factors that affect excavation of the material.

The properties used to evaluate the soil as a source of gravel are gradation of grain sizes (as indicated by the Unified classification of the soil), the thickness of suitable material, and the content of rock fragments. If the bottom layer of the soil contains gravel, the soil is considered a likely source regardless of thickness. The assumption is that the gravel layer below the depth of observation exceeds the minimum thickness. The ratings are for the whole soil, from the surface to a depth of about 6 feet. Coarse fragments of soft bedrock, such as shale and siltstone, are not considered to be gravel.

The soils are rated "good," "fair," or "poor" as potential sources of gravel. A rating of "good" or "fair" means that the source material is likely to be in or below the soil. The bottom layer and the thickest layer of the soils are assigned numerical ratings. These ratings indicate the likelihood that the layer is a source of gravel. The number 0.00 indicates that the layer is a poor source. The number 1.00 indicates that the layer is a good source. A number between 0.00 and 1.00 indicates the degree to which the layer is a likely source.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Ground-based Solar Arrays, Ballast Anchor Systems

Ground-based solar arrays are sets of photovoltaic panels that are not situated on a building or pole. These installations consist of a racking system that holds the panel in the desired orientation and the foundation structures that hold the racking system to the ground. Two basic methods are used to hold the systems to the ground, based on site conditions and cost. One method employs driven piles, screw augers, or concrete piers that penetrate into the soil to provide a stable foundation. The ease of installation and general site suitability of soil-penetrating anchoring systems depends on soil characteristics such as rock fragment content, soil depth, soil strength, soil corrosivity, shrink-swell tendencies, and drainage. The other basic anchoring system utilizes precast ballasted footings or ballasted trays on the soil surface to make the arrays too heavy to move. The site considerations that impact both basic systems are slope, slope aspect, wind speed, land surface shape, flooding, and ponding. Other factors that will contribute to the function of a solar power array include daily hours of sunlight and shading from hills, trees, or buildings.

Ballast anchor systems can be used in some places where soil-penetrating systems cannot, such as in shallow or stony soil. Also, since they do not penetrate the soil, ballast systems can be used where the soil is contaminated and disturbance is to be avoided. The soil in the area must have sufficient strength to be able to support the vehicles that haul the ballast and the machinery to install it.

Soils can be a non-member, partial member or complete members of the set of soils that are limited for "Ground-based Solar Panel Arrays". If a soil's property within 150 cm (60 inches) of the soil surface has a membership indices greater than zero, then that soil property is limiting and the soil restrictive feature is identified. The overall interpretive rating assigned is the maximum membership indices of each soil interpretive property that comprise the "Ground-based Solar Panel Arrays" interpretive rule. Minor restrictive soil features are identified but not considered as part of the overall rating process. These restrictive features could be important factors where the major restrictive features are overcome through design application.

Soils are placed into interpretive rating classes per their rating indices. These are not limited (rating index = 0), somewhat limited (rating index greater than 0 and less than 1.0), or very limited (rating index = 1.0).

Numerical ratings indicate the degree of limitation. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the least similarity to a good site (1.0) and the point at which the soil feature is very much like known good sites (0).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Canada, S. 2012. Corrosion impacts on steel piles. Solarpro. Solarprofessional.com.

Romanoff, Melvin. 1962. Corrosion of Steel Pilings in Soils. Journal of Research of the National Bureau of Standards. (Volume 66C, No. 3). July/September, 1962.

Ground-based Solar Arrays, Soil-penetrating Anchor Systems

Ground-based solar arrays are sets of photovoltaic panels that are not situated on a building or pole. These installations consist of a racking system that holds the panel in the desired orientation and the foundation structures that hold the racking system to the ground. Two basic methods are used to hold the systems to the ground, based on site conditions and cost. One method employs driven piles, screw augers, or concrete piers that penetrate into the soil to provide a stable foundation. The ease of installation and general site suitability of soil-penetrating anchoring systems depends on soil characteristics such as rock fragment content, soil depth, soil strength, soil corrosivity, shrink-swell tendencies, and drainage. The other basic anchoring system utilizes precast ballasted footings or ballasted trays on the soil surface to make the arrays too heavy to move. The site considerations that impact both basic systems are slope, slope aspect, wind speed, land surface shape, flooding, and ponding. Other factors that will contribute to the function of a solar power array include daily hours of sunlight and shading from hills, trees or buildings.

Soil-penetrating anchoring systems can be used where the soil conditions are not limited. Installation of these systems requires some power equipment for hauling components and either driving piles, turning helices, or boring holes to install the anchoring apparatus.

Soils can be a non-member, partial member or complete members of the set of soils that are limited for "Ground-based Solar Panel Arrays". If a soil's property within 150 cm (60 inches) of the soil surface has a membership indices greater than zero, then that soil property is limiting and the soil restrictive feature is identified. The overall interpretive rating assigned is the maximum membership indices of each soil interpretive property that comprise the "Ground-based Solar Panel Array" interpretive rule. Minor restrictive soil features are identified but not considered as part of the overall rating process. These restrictive features could be important factors where the major restrictive features are overcome through design application.

Soils are placed into interpretive rating classes per their rating indices. These are not limited (rating index = 0), somewhat limited (rating index greater than 0 and less than 1.0), or very limited (rating index = 1.0).

Numerical ratings indicate the degree of limitation. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the least similarity to a good site (1.00) and the point at which the soil feature is very much like known good sites (0).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Canada, S. 2012. Corrosion impacts on steel piles. Solarpro. Solarprofessional.com.

Romanoff, Melvin. 1962. Corrosion of Steel Pilings in Soils. Journal of Research of the National Bureau of Standards. (Volume 66C, No. 3). July/September, 1962.

This interpretation rates soils for their use in establishing and maintaining turf for lawns and golf fairways and ornamental trees and shrubs for residential or commercial landscaping. Lawns and landscaping require soils on which turf and ornamental trees and shrubs can be established and maintained. Golf fairways are subject to heavy foot traffic and some light vehicular traffic. Cutting or filling may be required.

The ratings are based on the use of soil material at the site, which may have been altered by some land smoothing. Irrigation may or may not be needed and is not a criterion in rating. The ratings are based on the soil properties that affect plant growth and trafficability after vegetation is established. The properties that affect plant growth are reaction; depth to a water table; ponding; depth to bedrock or a cemented pan; the available water capacity in the upper 40 inches; the content of salts, sodium, or calcium carbonate; and sulfidic materials. The properties that affect trafficability are flooding, depth to a water table, ponding, slope, stoniness, and the amount of sand, clay, or organic matter in the surface layer. The suitability of the soil for traps, tees, roughs, and greens is not considered in the ratings.

Not considered in the ratings, but important in evaluating a site, are the location and accessibility of the area, the size and shape of the area and its scenic quality, vegetation, access to water, potential water impoundment sites, and access to public sewer lines. Soils that are subject to flooding are limited by the duration and intensity of flooding and the season when flooding occurs. In planning for lawns, landscaping, or golf fairways, onsite assessment of the height, duration, intensity, and frequency of flooding is essential.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Local roads and streets have an all-weather surface and carry automobile and light truck traffic all year. They have a subgrade of cut or fill soil material; a base of gravel, crushed rock, or soil material stabilized by lime or cement; and a surface of flexible material (asphalt), rigid material (concrete), or gravel with a binder. The ratings are based on the soil properties that affect the ease of excavation and grading and the traffic-supporting capacity. The properties that affect the ease of excavation and grading are depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, depth to a water table, ponding, flooding, the amount of large stones, and slope. The properties that affect the traffic-supporting capacity are soil strength (as inferred from the AASHTO group index number), subsidence, linear extensibility (shrink-swell potential), the potential for frost action, depth to a water table, and ponding.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Roadfill is soil material that is excavated in one place and used in road embankments in another place. The soils are rated as a source of roadfill for low embankments, generally less than 6 feet high and less exacting in design than higher embankments. The ratings are for the whole soil, from the surface to a depth of about 5 feet. It is assumed that soil layers will be mixed when the soil material is excavated and spread.

The soils are rated "good," "fair," or "poor" as potential sources of roadfill. The ratings are based on the amount of suitable material and on soil properties that affect the ease of excavation and the performance of the material after it is in place. The thickness of the suitable material is a major consideration. The ease of excavation is affected by large stones, depth to a water table, and slope. How well the soil performs in place after it has been compacted and drained is determined by its strength (as inferred from the AASHTO classification of the soil) and linear extensibility (shrink-swell potential). Normal compaction, minor processing, and other standard construction practices are assumed.

Numerical ratings between 0.00 and 0.99 are given after the specified features. These numbers indicate the degree to which the features limit the soils as sources of roadfill. The lower the number, the greater the limitation.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Sand is a natural aggregate (0.05 millimeter to 2 millimeters in diameter) suitable for commercial use with a minimum of processing. It is used in many kinds of construction. Specifications for each use vary widely. Only the probability of finding material in suitable quantity is evaluated. The suitability of the material for specific purposes is not evaluated, nor are factors that affect excavation of the material.

The properties used to evaluate the soil as a source of sand are gradation of grain sizes (as indicated by the Unified classification of the soil), the thickness of suitable material, and the content of rock fragments. If the bottom layer of the soil contains sand, the soil is considered a likely source regardless of thickness. The assumption is that the sand layer below the depth of observation exceeds the minimum thickness. The ratings are for the whole soil, from the surface to a depth of about 6 feet.

The soils are rated "good," "fair," or "poor" as potential sources of sand. A rating of "good" or "fair" means that sand is likely to be in or below the soil. The bottom layer and the thickest layer of the soil are assigned numerical ratings. These ratings indicate the likelihood that the layer is a source of sand. The number 0.00 indicates that the layer is a "poor source." The number 1.00 indicates that the layer is a "good source." A number between 0.00 and 1.00 indicates the degree to which the layer is a likely source.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Septic tank absorption fields are areas in which effluent from a septic tank is distributed into the soil through subsurface tiles or perforated pipe. Only that part of the soil between depths of 24 and 60 inches is evaluated. The ratings are based on the soil properties that affect absorption of the effluent, construction and maintenance of the system, and public health. Saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, and flooding affect absorption of the effluent. Stones and boulders, ice, and bedrock or a cemented pan interfere with installation. Subsidence interferes with installation and maintenance. Excessive slope may cause lateral seepage and surfacing of the effluent in downslope areas.

Some soils are underlain by loose sand and gravel or fractured bedrock at a depth of less than 4 feet below the distribution lines. In these soils the absorption field may not adequately filter the effluent, particularly when the system is new. As a result, the ground water may become contaminated.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Sewage lagoons are shallow ponds constructed to hold sewage while aerobic bacteria decompose the solid and liquid wastes. Lagoons should have a nearly level floor surrounded by cut slopes or embankments of compacted soil. Nearly impervious soil material for the lagoon floor and sides is required to minimize seepage and contamination of ground water. Considered in the ratings are slope, saturated hydraulic conductivity (Ksat), depth to a water table, ponding, depth to bedrock or a cemented pan, flooding, large stones, and content of organic matter.

Ksat is a critical property affecting the suitability for sewage lagoons. Most porous soils eventually become sealed when they are used as sites for sewage lagoons. Until sealing occurs, however, the hazard of pollution is severe. Soils that have a Ksat rate of more than 14 micrometers per second are too porous for the proper functioning of sewage lagoons. In these soils, seepage of the effluent can result in contamination of the ground water. Ground-water contamination is also a hazard if fractured bedrock is within a depth of 40 inches, if the water table is high enough to raise the level of sewage in the lagoon, or if floodwater overtops the lagoon.

A high content of organic matter is detrimental to proper functioning of the lagoon because it inhibits aerobic activity. Slope, bedrock, and cemented pans can cause construction problems, and large stones can hinder compaction of the lagoon floor. If the lagoon is to be uniformly deep throughout, the slope must be gentle enough and the soil material must be thick enough over bedrock or a cemented pan to make land smoothing practical.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Shallow excavations are trenches or holes dug to a maximum depth of 5 or 6 feet for graves, utility lines, open ditches, or other purposes. The ratings are based on the soil properties that influence the ease of digging and the resistance to sloughing. Depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, the amount of large stones, and dense layers influence the ease of digging, filling, and compacting. Depth to the seasonal high water table, flooding, and ponding may restrict the period when excavations can be made. Slope influences the ease of using machinery. Soil texture, depth to the water table, and linear extensibility (shrink-swell potential) influence the resistance to sloughing.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Small commercial buildings are structures that are less than three stories high and do not have basements. The foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of 2 feet or at the depth of maximum frost penetration, whichever is deeper. The ratings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs. The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility (shrink-swell potential), and compressibility (which is inferred from the Unified classification of the soil). The properties that affect the ease and amount of excavation include flooding, depth to a water table, ponding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Ground-based Solar Arrays, Ballast Anchor Systems

Ground-based solar arrays are sets of photovoltaic panels that are not situated on a building or pole. These installations consist of a racking system that holds the panel in the desired orientation and the foundation structures that hold the racking system to the ground. Two basic methods are used to hold the systems to the ground, based on site conditions and cost. One method employs driven piles, screw augers, or concrete piers that penetrate into the soil to provide a stable foundation. The ease of installation and general site suitability of soil-penetrating anchoring systems depends on soil characteristics such as rock fragment content, soil depth, soil strength, soil corrosivity, shrink-swell tendencies, and drainage. The other basic anchoring system utilizes precast ballasted footings or ballasted trays on the soil surface to make the arrays too heavy to move. The site considerations that impact both basic systems are slope, slope aspect, wind speed, land surface shape, flooding, and ponding. Other factors that will contribute to the function of a solar power array include daily hours of sunlight and shading from hills, trees, or buildings.

Ballast anchor systems can be used in some places where soil-penetrating systems cannot, such as in shallow or stony soil. Also, since they do not penetrate the soil, ballast systems can be used where the soil is contaminated and disturbance is to be avoided. The soil in the area must have sufficient strength to be able to support the vehicles that haul the ballast and the machinery to install it.

Soils can be a non-member, partial member or complete members of the set of soils that are limited for "Ground-based Solar Panel Arrays". If a soil's property within 150 cm (60 inches) of the soil surface has a membership indices greater than zero, then that soil property is limiting and the soil restrictive feature is identified. The overall interpretive rating assigned is the maximum membership indices of each soil interpretive property that comprise the "Ground-based Solar Panel Arrays" interpretive rule. Minor restrictive soil features are identified but not considered as part of the overall rating process. These restrictive features could be important factors where the major restrictive features are overcome through design application.

Soils are placed into interpretive rating classes per their rating indices. These are not limited (rating index = 0), somewhat limited (rating index greater than 0 and less than 1.0), or very limited (rating index = 1.0).

Numerical ratings indicate the degree of limitation. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the least similarity to a good site (1.0) and the point at which the soil feature is very much like known good sites (0).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Canada, S. 2012. Corrosion impacts on steel piles. Solarpro. Solarprofessional.com.

Romanoff, Melvin. 1962. Corrosion of Steel Pilings in Soils. Journal of Research of the National Bureau of Standards. (Volume 66C, No. 3). July/September, 1962.

Ground-based Solar Arrays, Soil-penetrating Anchor Systems

Ground-based solar arrays are sets of photovoltaic panels that are not situated on a building or pole. These installations consist of a racking system that holds the panel in the desired orientation and the foundation structures that hold the racking system to the ground. Two basic methods are used to hold the systems to the ground, based on site conditions and cost. One method employs driven piles, screw augers, or concrete piers that penetrate into the soil to provide a stable foundation. The ease of installation and general site suitability of soil-penetrating anchoring systems depends on soil characteristics such as rock fragment content, soil depth, soil strength, soil corrosivity, shrink-swell tendencies, and drainage. The other basic anchoring system utilizes precast ballasted footings or ballasted trays on the soil surface to make the arrays too heavy to move. The site considerations that impact both basic systems are slope, slope aspect, wind speed, land surface shape, flooding, and ponding. Other factors that will contribute to the function of a solar power array include daily hours of sunlight and shading from hills, trees or buildings.

Soil-penetrating anchoring systems can be used where the soil conditions are not limited. Installation of these systems requires some power equipment for hauling components and either driving piles, turning helices, or boring holes to install the anchoring apparatus.

Soils can be a non-member, partial member or complete members of the set of soils that are limited for "Ground-based Solar Panel Arrays". If a soil's property within 150 cm (60 inches) of the soil surface has a membership indices greater than zero, then that soil property is limiting and the soil restrictive feature is identified. The overall interpretive rating assigned is the maximum membership indices of each soil interpretive property that comprise the "Ground-based Solar Panel Array" interpretive rule. Minor restrictive soil features are identified but not considered as part of the overall rating process. These restrictive features could be important factors where the major restrictive features are overcome through design application.

Soils are placed into interpretive rating classes per their rating indices. These are not limited (rating index = 0), somewhat limited (rating index greater than 0 and less than 1.0), or very limited (rating index = 1.0).

Numerical ratings indicate the degree of limitation. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the least similarity to a good site (1.00) and the point at which the soil feature is very much like known good sites (0).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Canada, S. 2012. Corrosion impacts on steel piles. Solarpro. Solarprofessional.com.

Romanoff, Melvin. 1962. Corrosion of Steel Pilings in Soils. Journal of Research of the National Bureau of Standards. (Volume 66C, No. 3). July/September, 1962.

Reclamation material is used in areas that have been drastically disturbed by surface mining or similar activities. When these areas are reclaimed, layers of soil material or unconsolidated geological material, or both, are replaced in a vertical sequence. The reconstructed soil favors plant growth. The ratings do not apply to quarries or other mined areas that require an offsite source of reconstruction material. The ratings are based on the soil properties that affect erosion and stability of the surface and the productive potential of the reclaimed soil. These properties include the content of sodium, salts, and calcium carbonate; reaction; available water capacity; erodibility; texture; content of rock fragments; and content of organic matter and other features that affect fertility.

The soils are rated "good," "fair," or "poor" as potential sources of reclamation material. The ratings are based on the amount of suitable material and on soil properties that affect the ease of excavation and the performance of the material after it is in place. The thickness of the suitable material is a major consideration. The ease of excavation is affected by large stones, depth to a water table, and slope. How well the soil performs in place after it has been compacted and drained is determined by its strength (as inferred from the AASHTO classification of the soil) and linear extensibility (shrink-swell potential). Normal compaction, minor processing, and other standard construction practices are assumed.

When the material is properly used in reclamation, a rating of "good" means that establishing and maintaining vegetation are relatively easy, that the surface is stable and resists erosion, and that the reclaimed soil has good potential productivity. A rating of "fair" means that vegetation can be established and maintained and the soil can be stabilized through modification of one or more properties. For satisfactory performance, it may be necessary to topdress with better suited material or add soil amendments. A rating of "poor" means that revegetation and stabilization are very difficult and costly. To establish and maintain vegetation, it is necessary to topdress with better suited material.

Numerical ratings between 0.00 and 0.99 are given after the specified features. These numbers indicate the degree to which the features limit the soils as sources of reclamation material. The lower the number, the greater the limitation.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Topsoil is used to cover an area so that vegetation can be established and maintained. The surface layer of most soils is generally preferred for topsoil because of its content of organic matter. Organic matter greatly increases the absorption and retention of moisture and nutrients for plant growth.

The upper 40 inches of a soil is evaluated for use as topsoil. Also evaluated is the reclamation potential of the borrow area. Normal compaction, minor processing, and other standard construction practices are assumed.

The soils are rated "good," "fair," or "poor" as potential sources of topsoil. The ratings are based on the soil properties that affect plant growth; the ease of excavating, loading, and spreading the material; and reclamation of the borrow area. Toxic substances, soil reaction, and the properties that are inferred from soil texture, such as available water capacity and fertility, affect plant growth. The ease of excavating, loading, and spreading is affected by rock fragments, slope, depth to a water table, soil texture, and thickness of suitable material. Reclamation of the borrow area is affected by slope, depth to a water table, rock fragments, depth to bedrock or a cemented pan, and toxic material.

Numerical ratings between 0.00 and 0.99 are given after the specified features. These numbers indicate the degree to which the features limit the soils as sources of topsoil. The lower the number, the greater the limitation.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Unpaved local roads and streets are those roads and streets that carry traffic year round but have a graded surface of local soil material or aggregate. Description:

Unpaved local roads and streets are those roads and streets that carry traffic year round but have a graded surface of local soil material or aggregate. The roads and streets consist of (1) the underlying local soil material, either cut or fill, which is called "the sub-grade"; (2) the surface, which may be the same as the subgrade or may have aggrate such as crushed limestone added.

They are graded to shed water, and conventional drainage measures are provided. These roads and streets are built mainly from the soil at the site. Soil interpretations for local roads and streets are used as a tool in evaluating soil suitability and identifying soil limitations for the practice. The rating is for soils in their present condition and does not consider present land use. Soil properties and qualities that affect local roads and streets are those that influence the ease of excavation and grading and the traffic-supporting capacity. The properties and qualities that affect the ease of excavation and grading are hardness of bedrock or a cemented pan, depth to bedrock or a cemented pan, depth to a water table, flooding, the amount of large stones, and slope. The properties that affect traffic-supporting capacity are soil strength as inferred from the AASHTO group index and the Unified classification, subsidence, shrink-swell behavior, potential frost action, and depth to the seasonal high water table. The dust generating tendacy of the soil is also considered.

For limitations affecting the construction of haul roads and log landings, the ratings are based on slope, flooding, permafrost, plasticity index, the hazard of soil slippage, content of sand, the Unified classification of the soil, rock fragments on or below the surface, depth to a restrictive layer that is indurated, depth to a water table, and ponding.

The ratings are both verbal and numerical. Rating class terms indicate the degree to which the soils are suited to this aspect of forestland management. The limitations are described as slight, moderate, or severe. A rating of "slight" indicates that no significant limitations affect construction activities. "Moderate" indicates that one or more limitations can cause some difficulty in construction. "Severe" indicates that one or more limitations can make construction very difficult or very costly.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Drought Vulnerable Soils

Even in a year, having normal precipitation or slightly less than normal, some soils are prone to having drought stress occur in the plants growing on them. Several conditions can allow this to happen. Most influential may be a relative lack of effective precipitation, as is estimated by subtracting the mean annual precipitation from an estimate of the annual evapotranspiration. Soils west of the 100th meridian frequently fall into this situation, especially at low elevations. Also, a soil may have an inherently low ability to store water. This is typical of sandy or shallow soils or soils having a high content of rock fragments. In this case, even though there may be significant rainfall, the soil matrix does not retain sufficient water for crop growth.

Topographic and climatic characteristics can be present to mitigate a soil's droughty tendacies. Some soils exist on water-gathering portions of the landscape and can thus support more plant growth than their similar neighbors because of run on. Some soils have a water table present within the rooting zone during the growing season to supply plant water needs. Finally, some soils exist in a climate where precipitation is much higher than evapotranspiration and the soil is nearly always moist. This can occur in cool climates at high elevations.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are vulnerable to drought. Numerical ratings indicate the degree of vulnerability associated with each soil or site feature. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature imparts the greatest degree of vulnerability (1.00) and the point at which the soil feature helps to mitigate drought vulnerability (0.00).

Verbal ratings are defined as follows:

Severely drought vulnerable (rating index equals 1.0). The soil and site properties present are such that the plants growing on the soil must be very drought tolerant even in years with normal amounts of rainfall. The soil may have very low water storage capacity (below 5 cm) or may be in an area of low annual precipitation or high annual temperature or both.

Drought vulnerable (rating index is greater than 0.67 but less than 1.0). The soil and site properties are such that drought conditions generally occur every year. The soil may have low water storage capacity (5 to 15 cm) and the site may have low annual precipitation or high annual temperature or both.

Moderately drought vulnerable (rating index is greater than 0.33 but less than 0.67). The soil and site proerties are such that in an average year, some water stress may occur, but in a good year, plant available water is generally adequate. Water storage is in the range of 15 to 25 cm. Rainfall and estimated potential evapotranspiration are nearly equal.

Somewhat drought vulnerable (rating index is greater than 0 but less than 0.33). These soils have greater than 25 cm of water storage and annual precipitation is generally adequate for plant growth. In dry years some water stress may occur.

Slightly drought vulnerable (rating index equals 0). These soils are either in lowlying parts of the landscape where plant roots may exploit near-surface ground water or are in areas where precipitation is much higher than potential evapotranspitration. In an extremely dry year plants may be water stressed on these soils.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Ratings for this interpretation indicate the suitability for use of forestland harvesting equipment. The ratings are based on slope, rock fragments on the surface, plasticity index, content of sand, the Unified classification of the soil, depth to a water table, and ponding. Standard rubber-tire skidders and bulldozers are assumed to be used for ground-based harvesting and transport.

The ratings are both verbal and numerical. Rating class terms indicate the degree to which the soils are suited to this aspect of forestland management. "Well suited" indicates that the soil has features that are favorable for the specified management aspect and has no limitations. Good performance can be expected, and little or no maintenance is needed. "Moderately suited" indicates that the soil has features that are moderately favorable for the specified management aspect. One or more soil properties are less than desirable, and fair performance can be expected. Some maintenance is needed. "Poorly suited" indicates that the soil has one or more properties that are unfavorable for the specified management aspect. Overcoming the unfavorable properties requires special design, extra maintenance, and costly alteration.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

FOR - Longleaf Pine Suitability

Summary:

Long leaf pine forest once encompassed more than 90 million acres across the Southeast, stretching from eastern Texas to southern Virginia. These forests represent some of the worlds most diverse ecosystems. Over the past two centuries, development, timbering and fire suppression reduced the longleaf pine range nearly 97%. Since 2010 National Cooperative Soil Survey and other partners have helped producers restore longleaf pine on more than 870,000 acres of private land with the Longleaf Pine Initiative (LLPI). This increased the range from 3 million to 5 million acres reversing a century long decline across the region.

The model developed here is meant to assist efforts in longleaf pine restoration. An interesting aspect of this model is that it does not predict the most productive sites for longleaf pine, but rather the sites where the species can outcompete other tree species, like oaks. Longleaf pine is a warm climate species that requires significant rainfall. The biologic range of the tree is constrained by the decreased rainfall in the west and the decreased temperature to the north. Longleaf pine generally leans toward drier sites, in terms of the frequency of ponding or flooding occurrence, despite the Latin name of palustris, which means swampy. The distribution of longleaf pine on the landscape indicates an overwhelming preference for deep, sandy soils, such as the Carolina Sandhills of the Coastal Plain. However, ample data exists to indicate that the species can also compete in the Valley and Ridge and in a limited area of the Piedmont. The tolerance of longleaf pine to soil wetness presents a conundrum. Well drained soils are preferred in most places. However, especially in Florida, stands of longleaf pine exist on poorly and very poorly drained soils, too. It is hypothesized that, apparently, high evapotranspiration can influence the occurrence of the tree in some circumstances. Longleaf pine can be found on a variety of soils in nature where they can successfully compete against other species of pines and oaks. Currently, the model examines the effect of soil texture, available water storage, bulk density, reaction, electrical conductivity, cation exchange capacity, saturated hydraulic conductivity, linear extensibility, organic matter content, and rock fragment content on the occurrence of longleaf pine.

Ratings

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are suited by all of the soil features that affect these uses. Numerical ratings indicate the degree of suitability of each soil or site feature. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest degree of suitability for the use (1.00) and the point at which the soil feature is not suited for the use (0.00).

Verbal ratings are defined as follows:

Well suited (rating index equals 1.0). The soil and site properties present are optimal for the occurrence of longleaf pine. These will likely be the best sites for restoration.

Suited (rating index is greater than 0.75 but less than 1.0). The soil and site properties are generally suited, but not optimal. The site may have seasonal saturation, or have soil chemical or physical properties that may slightly limit the competitiveness of longleaf pine. These sites should also be considered for restoration.

Somewhat suited (rating index is greater than 0.3 but less than 0.75). The soil and site properties are generally suited, but not well suited. The site may have seasonal saturation, or have soil chemical or physical properties that may limit the growth of longleaf pine. The tree will grow and produce on these sites, but may be outcompeted by other species.

Poorly suited (rating index is greater than 0 but less than 0.3). The suitability of the site is marginal for the growth of longleaf pine.

Not suited (rating index equals 0). The soil is rendered unsuitable for longleaf pine growth due to very unfavorable conditions, such as severe wetness, or poor physical and chemical soil properties.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Walker, Laurence C. and Wiant, Harry V. Jr., "Forestry Bulletin No. 11: Silviculture of Longleaf Pine" (1966). Forestry Bulletins No. 1-25, 1957-1972. 10. https://scholarworks.sfasu.edu/forestrybulletins/10.

Boyer, W. D. 1985. Longleaf Pine. Accessed 06 06, 2015. http://www.na.fs.fed.us/spfo/pubs/silvics_manual/Volume_1/pinus/palustris.htm.

The Longleaf Alliance. 2016. The Longleaf Alliance. Accessed 10 30, 2016. http://www.longleafalliance.org/.

The Nature Conservancy. 2022. Longleaf Pine: A Tree for Our Time. September 28. Accessed February 1, 2023. https://www.nature.org/en-us/what-we-do/our-priorities/protect-water-and-land/land-and-waterstories/longleaf-pine-restoration/

North Carolina Forest Service. 2011. Longleaf Pine Leaflet. LL#3

Craul, Phillip J.; Kush, John S.; Boyer, William D. 2005. Longleaf pine site zones. Gen. Tech. Rep. SRS-89. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 23 p.

Addington et al, 2015. Robert N. Addington; Benjamin O. Knapp; Geoffrey G. Sorrell; Michele L. Elmore; G. Geoff Wang; Joan L. Walker. Factors affecting broadleaf woody vegetation in upland pine forests managed for longleaf pine restoration. Forest Ecology and Management, 354 (2015), pp 130-138.

Mitchell, T.J., Patterson, T.W. & Knapp, P.A. Comparison of climate growth responses of montane and piedmont longleaf pine (Pinus palustris Mill.) chronologies in North Carolina. Trees 33, 615620 (2019). https://doi.org/10.1007/s00468-019-01823-8.

Samuelson, L. J., Stokes, T. A., Ramirez, M. R., & Mendonca, C. C. (2019). Drought tolerance of a Pinus palustris plantation. Forest Ecology and Management, 451, 117557. https://doi.org/10.1016/j.foreco.2019.117557

Prior, S. A., Runion, G. B., Mitchell, R. J., Rogers, H. H., & Amthor, J. S. (1997). Effects of atmospheric CO2 on Longleaf Pine: Productivity and allocation as influenced by nitrogen and water. Tree Physiology, 17(6), 397 405. https://doi.org/10.1093/treephys/17.6.397

Moorhead, D. J., & Ruter, J. M. (1970, January 1). Water quality in the production of containerized longleaf pine seedlings. US Forest Service Research and Development. Retrieved February 2, 2023, from https://www.fs.usda.gov/treesearch/pubs/5047

Weisman, K., Lord, L., & Lerner, J. (n.d.). Longleaf pine - a tall drink of water. Savannah River Clean Water. Retrieved February 2, 2023, from https://savannahrivercleanwater.org/wp-content/uploads/2022/04/LongleafPine-A-Tall-Drink-of-Water.pdf

Svehla, R., & Farrish, K. (n.d.). Soil Morphological, Physical, and Chemical Parameters Affecting Longleaf Pine (Pinus palustris) Site Quality and Ecosystem Restoration Potential in East Texas. SFA ScholarWorks. Retrieved February 2, 2023, from https://scholarworks.sfasu.edu/cgi/viewcontent.cgi?article=1151&context=etds.

Boyer, W. D. (n.d.). Longleaf Pine. Pinus palustris mill. Retrieved February 2, 2023, from https://www.srs.fs.usda.gov/pubs/misc/ag_654/volume_1/pinus/palustris.htm

Fan, Z., Yang, S., Kush, J. M., & Narine, L. (2022). Natural regeneration dynamics of longleaf pine under frequent, low-intensity prescribed fires in southern Alabama, USA. Forest Science, 68(5-6), 496507. https://doi.org/10.1093/forsci/fxac032

Freeze injury alert. The Longleaf Alliance. (2022, December 22). Retrieved February 2, 2023, from https://longleafalliance.org/freezeinjury/#:~:text=When%20temperatures%20drop%20for%20extended%20periods%2C%20or%20when,If%20you%20haven%E2%80%99t%20planted%20yet%2C%20protect%20your%20seedlings.

Barlow, P. by: B. (2022, August 25). Planting longleaf pine in the Southern Urban Landscape. Alabama Cooperative Extension System. Retrieved February 2, 2023, from https://www.aces.edu/blog/topics/forestry/plantinglongleaf-pine-in-the-southern-urbanlandscape/#:~:text=Grows%20wells%20on%20moist%20soils%3B%20however%2C%20does%20not,with%20limited%20overhead%20competition.%20Site%20preparation%20and%20planting

LL-#3 April 2011 - ncforestservice.gov. North Carolina Forest Service. (2011, April). Retrieved February 3, 2023, from https://ncforestservice.gov/publications/LongleafLeaflets/LL03.pdf

The ratings in this interpretation indicate the potential for damage to nutrient, physical, and biotic soil characteristics by fire. The ratings involve an evaluation of the potential impact of prescribed fires or wildfires that are intense enough to remove the duff layer and consume organic matter in the surface layer.

The ratings are based on texture of the surface layer, content of rock fragments and organic matter in the surface layer, thickness of the surface layer, and slope.

The ratings are both verbal and numerical. The soils are described as having a "low," "moderate," or "high" potential for this kind of damage. "Low" indicates that fire damage is unlikely. Good performance can be expected, and little or no maintenance is needed. "Moderate" indicates that fire damage can occur because one or more soil properties are less than desirable. Fair performance can be expected, and some maintenance is needed. "High" indicates that fire damage can occur because of one or more soil properties and that overcoming the unfavorable properties requires special design, extra maintenance, and costly alteration.

Numerical ratings indicate gradations between the point at which the potential for fire damage is highest (1.00) and the point at which the potential is lowest (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings in this interpretation indicate the likelihood of death of naturally or artificially propagated tree seedlings, as influenced by soil characteristics, physiographic features, and climatic conditions. Considered in the ratings are flooding, ponding, depth to a water table, content of lime, reaction, available water capacity, soil moisture regime, soil temperature regime, aspect, and slope.

The ratings are both verbal and numerical. The soils are described as having a "low," "moderate," or "high" potential for seedling mortality. "Low" indicates that seedling mortality is unlikely. Good performance can be expected, and little or no maintenance is needed. "Moderate" indicates that seedling mortality can occur because one or more soil properties are less than desirable. Fair performance can be expected, and some maintenance is needed. "High" indicates that seedling mortality can occur because of one or more soil properties and that overcoming the unfavorable properties requires special design, extra maintenance, and costly alteration.

Numerical ratings indicate gradations between the point at which the potential for seedling mortality is highest (1.00) and the point at which the potential is lowest (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Shortleaf pine littleleaf disease susceptibility

This interpretation rates soils for their susceptibility to foster the occurrence of littleleaf disease (LLD) which is a limitation for shortleaf pine growth. LLD is of great concern in shortleaf pine management because it occurs in the marketable age of the tree or can interfere with other management objectives. The soil and site properties evaluated in the interpretation include Ksat, wetness, pH in upper horizons, flooding duration and frequency, erosion class, and shrink-swell. Criteria were developed by looking at the extent and type of soils where LLD is a problem.

Shortleaf pine is affected by littleleaf disease and is the most serious disease of shortleaf pine in the Southern United States. Affected trees have reduced growth rates and usually die within 6 years. The disease is facilitated by a complex of factors including the fungus Phytophthora cinnamomi Rands, low soil nitrogen, and poor soil drainage. Phytophthora cinnamomi, further stresses the tree, and infects the rootlets. Often, microscopic roundworms called nematodes and species of the fungal genus Pythium are associated with the disease. A root rot fungus eventually kills the tree.

Affected stands are found in the Piedmont area from Virginia to Mississippi, with additional scattered pockets of the disease in eastern Tennessee and southeastern Kentucky. The disease has its greatest impact in Alabama, Georgia, and South Carolina.

Shortleaf pine is more susceptible to LLD than other southern pines, but the disease is also present in loblolly (Pinus taeda), slash (Pinus elliottii), and virginia pine (Pinus virginiana).

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the characteristics of the site and soils influence the progression of the disease. "High susceptibility for littleleaf disease" indicates that the soil has features that are favorable for the growth of the pathogen. "Moderate susceptibility for littleleaf disease" indicates that the soil has one or more features that are favorable for the development of the disease. "Low susceptibility for littleleaf disease" indicates that characteristics of the soil and site do not favor the development of the disease.

Numerical ratings indicate the degree of suitability. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the lowest tendency to foster the disease (0.00) and the point at which the soil and site features are very much like known susceptible sites (1.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented

References:

Belanger. R.P., Hedden, R.L., and Tainter, F.H. 1986. Managing Piedmont Forests to Reduce Losses from the Littleleaf Disease-Southern Pine Beetle Complex. Forest Service. Cooperative State Research Service. Ag Handbook 649.

Boggessm, W.R., and Newman, R.R. 1947. Occurrence of littleleaf disease of pine and its effects on forestry in Alabama. Agriculture experiment station of the Alabama Polytechnic Institute. Auburn, Alabama. Circular No. 94.

Campbell, W.A., Copeland, O.L., and Hepting, G.H. 1953. Littleleaf Disease of Loblolly and Shortleaf Pine. Circ. 940.. 14p.

Campbell, W.A. and Copeland, O.L. 1954. Managing Shortleaf Pine in Littleleaf Disease Areas. Station Paper No. 25. Asheville NC;. Forest Service, Southern Forest Experiment Station.

Copeland, O.L. and McAlpine, R.G. 1955. The Interrelations of Littleleaf, Site Index, Soil, and Ground Cover in Piedmont Shortleaf Pine Stands. Ecology. 36, 4: 635-641.

Croll, P.M., Oak, S.W., and Holzman, S. 1992. Monitoring Forest Health in the Southern Region Southern Forest Atlas Littleleaf Disease Layer.

Douce, G.K., Moorhead, D.J., and Bargeron, C.T. 2002. Forest Pest Control: Littleleaf Disease. Bugwood. The University of Georgia Bugwood Network, College of Agricultural and Environmental Sciences, Forest Service Forest Health Protection Service. Special Bulletin 16, Revised January 2002. Online: http://www.bugwood.org/pestcontrol/diseases.html

Grand, L.F.,Hodges, C. S., and Jones, R. K. 2001. Some Common Pine Diseases in North Carolina: Littleleaf Disease. NC State Plant Pathology Extension. Online: http://www.ces.ncsu.edu/depts/pp/notes/Ornamental/odin19/od19.htm

Mistretta, P.A. Littleleaf Disease. Forest Insect and Disease Leaflet 20.. Forest Service, Southern Region.

Oak, S. W. 1985. Adaptation of Littleleaf Disease Hazard Rating for Use in Forest Management in South Carolina National Forests. In Proceedings, Integrated Pest Management Research Symposium. April 15-18, 1985, Asheville, NC. p. 246-251. Branhim, S.J. and Thatcher, R.C., eds. Gen Tech Rep. S0-56. New Orleans LA;. Forest Service, Southern Forest Experiment Station.

11Oak, S.W. and Tainter, F.H. 1988. How to Identify and Control Littleleaf Disease. Protection Rep. R8-PR 12. Atlanta GA;. Forest Service, Southern Region. 14p.

Roth, E.R., Toole, R.E., and Hepting, G.H. 1948. Nutritional Aspects of the Littleleaf Disease of Pine. Journal of Forestry. 46:578-587.

Forest health: Common Disease Problems, Littleleaf Disease. 2014. University of Arkansas Cooperative Extension. http://www.uaex.edu/environment-nature/forestry/health/disease-problems.aspx

Stressors of Pine Forests: Littleleaf Disease. Forest Service. Forest Health Protection, Southern Region. Online: http://216.166.86.145/hosf/littleaf.htm

Root Diseases: Little Leaf Disease. 2011. Auburn University. Online: https://fp.auburn.edu/sfws/enebak/ForestHealth/little/little.html.

FOR - Shortleaf Pine Suitability

Summary:

Shortleaf pine (Pinus echinata) is an important timber species in the southeastern United States. The species is adapted to a wide variety of soils and climates and is found in 22 states, from southern New York to eastern Texas. The seedlings of this tree have a distinctive double crook at or just below the forest floor which allows the small trees that have top-killed by fire to resprout. This species also performs a number of ecosystem services. When fire frequency is close to the natural regime, shortleaf pine stands can make a savannah which fosters a variety of habitats and species, including the endangered red-cockaded woodpecker.

The model presented here is meant to assist efforts in shortleaf pine restoration. An interesting aspect of this model is that it does not predict the most productive sites for shortleaf pine, but rather the sites where the species can outcompete other tree species, like oaks. The biologic range of the tree is constrained by the decreased rainfall in the west and the decreased temperature to the north. Shortleaf pine generally leans toward drier sites, in terms of the frequency of ponding or flooding occurrence. The distribution of shortleaf pine on the landscape indicates an overwhelming preference for deep, well-drained soils. Shortleaf pine can be found on a variety of soils in nature where they can successfully compete against other species of pines and oaks. Currently, the model examines the effect of soil texture, available water storage, bulk density, reaction, electrical conductivity, cation exchange capacity, saturated hydraulic conductivity, linear extensibility, organic matter content, and rock fragment content on the occurrence of shortleaf pine.

Ratings

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are suited by all of the soil features that affect these uses. Numerical ratings indicate the degree of suitability of each soil or site feature. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest degree of suitability for the use (1.00) and the point at which the soil feature is not suited for the use (0.00).

Verbal ratings are defined as follows:

Well suited (rating index equals 1.0). The soil and site properties present are optimal for the occurrence of shortleaf pine. These will likely be the best sites for restoration.

Suited (rating index is greater than 0.75 but less than 1.0). The soil and site properties are generally suited, but not optimal. The site may have seasonal saturation, or have soil chemical or physical properties that may slightly limit the competitiveness of shortleaf pine. These sites should also be considered for restoration.

Somewhat suited (rating index is greater than 0.3 but less than 0.75). The soil and site properties are generally suited, but not well suited. The site may have seasonal saturation, or have soil chemical or physical properties that may limit the growth of shortleaf pine. The tree will grow and produce on these sites, but may be outcompeted by other species.

Poorly suited (rating index is greater than 0 but less than 0.3). The suitability of the site is marginal for the growth of shortleaf pine.

Not suited (rating index equals 0). The soil is rendered unsuitable for shortleaf pine growth due to very unfavorable conditions, such as severe wetness, or poor physical and chemical soil properties.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Hedrick, Larry D.; Bukenhofer, George A.; Montague, Warren G.; Pell, William F.; Guldin, James M. 2007. Shortleaf pine-bluestem restoration in the Ouachita National Forest. In: Shortleaf pine restoration and ecology in the Ozarks: proceedings of a symposium: 206-213.

Kabrick, John and David Larsen. 1999. Aspect affects oak and pine basal area and site index in Ozark forests. Missouri Department of Conservation. Report #2.

Mattoon, W. R. 1915 Life history of shortleaf pine. Bulletin of the US Department of Agriculture, No. 244. Washington, D.C. 46 pp.

North Carolina Forest Service. 2016. Silvics of shortleaf pine. SL-01. Walker, Laurence C. and Wiant, Harry V. Jr, "Forestry Bulletin No. 9: Silviculture of Shortleaf Pine" (1966). Forestry Bulletins No. 1-25, 1957-1972. 8. https://scholarworks.sfasu.edu/forestrybulletins/8.

This interpretation is designed to predict the potential for soil compaction from operation of ground-based equipment for forest harvesting and site preparation activities when soils are moist. Soils are rated based on their susceptibility to compaction from the operation of ground-based equipment for planting, harvesting, and site preparation activities. Soil compaction is the process in which soil particles are pressed together more closely than in the original state. Typically, the soil must be moist to be compacted because the mineral grains must slide together. Compaction reduces the abundance mostly of large pores in the soil by damaging the structure of the soil. This produces several effects that are unwanted in forest soils since large pores are most effective at transmitting water and air through the soil. Compaction also increases the soil strength, which can limit root penetration and growth. The ability of soil to hold water is adversely affected by compaction since the large pores hold water. The degree of compaction of a soil is measured by its bulk density, which is the mass per unit volume, generally expressed in grams per cubic centimeter.

Compacted soils are less favorable for good plant growth because of high soil bulk density and hardness, reduced pore space, and poor aeration and drainage. Root penetration and growth is decreased in compacted soils because the hardness or strength of these soils prevents the expansion of roots. Supplies of air, water, and nutrients that roots need are also reduced when compaction decreases soil porosity and drainage.

Interpretative ratings are based on soil properties in the upper 12 inches of the profile. Factors considered are soil texture, soil organic matter content, soil structure, rock fragment content, and the existing bulk density. Each of these properties contributes to a soils ability to resist compaction. Organic matter in the soil provides resistance to compaction and the resilience to overcome the effects with time. Soil structure adds strength through discrete aggregates; it is the aggregates that are deformed or destroyed by the forces of compaction, thus strong soil structure lowers the susceptibility to compaction. Similarly, rock fragments in the soil can bridge and provide a framework to resist compaction. Finally, if a soil is already dense, further compaction is more difficult.

The ratings are both verbal and numerical. Rating class terms indicate the soil compaction potential.

Definitions of the ratings:

Low - The potential for compaction is insignificant. The soil is able to support standard equipment with minimal compaction. The soil is moisture insensitive, exhibiting only small changes in density with changing moisture content.

Medium - The potential for compaction is significant. The growth rate of seedlings may be reduced following compaction. After the initial compaction (i.e., the first equipment pass), the soil is able to support standard equipment with only minimal increases in soil density. The soil is intermediate between moisture insensitive and moisture sensitive.

High - The potential for compaction is very significant. The growth rate of seedlings will be reduced following compaction. After initial compaction, the soil is still able to support standard equipment but will continue to compact with each subsequent pass of the equipment. The soil is moisture sensitive, exhibiting large changes in density with changing moisture content.

Numerical ratings indicate the soil compaction potential. The ratings are shown in decimal fractions ranging from 1.00 to 0.00. They indicate gradations between the point where compaction potential is highest (1.00) and the point at which compaction potential is lowest (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Adams, P.W. 1981. Compaction of forest soils. Oregon State University Extension Publication PNW 217.

Adams, P.W. 1998. Soil compaction on woodland properties. Oregon State University Extension Publication EC 1109.

Boyer, D. 1997. Guidelines for soil resource protection and restoration for timber harvest and post-harvest activities. U.S Forest Service, Pacific Northwest Region, Watershed Management.

Froehlich, H.A., and D.H. McNab. 1983. Minimizing soil compaction in Pacific Northwest forests. Proceedings of Sixth North American Forest Soils Conference, University of Tennessee.

Geist, J.M., J.W. Hazard, and K.W. Seidel. 1989. Assessing physical conditions of some Pacific Northwest volcanic ash soils after forest harvest. Soil Science Society of America Journal 53:946-950.

Page-Dumrose, D.S. 1993. Susceptibility of volcanic ash influenced soils in northern Idaho to mechanical compaction. U.S. Forest Service Intermountain Research Station. Research Note INT-409.

This interpretation is designed to predict the hazard for soil displacement from operation of ground-based equipment for forest harvesting and site preparation activities whether the soils are dry or moist. Displacement is the horizontal movement of soil caused by scraping or machine gouging. Displacement can remove the organic forest litter and upper portions of the mineral surface layer, reducing the availability of plant nutrients and the soil’s water-holding capacity. This results in a loss of site productivity for forest vegetation.

Displacement most commonly occurs during slash disposal and site preparation activities when a blade attachment is used with equipment rather than a brush rake attachment. Tractors maneuvering on dry, loose soil can also cause displacement.

Interpretation ratings are based on soil properties in the upper 12 inches of the profile. Factors considered are soil texture, rock fragment content, and thickness of surface layers with at least 1 percent organic matter. Initial ratings are based on the following soil texture groups:

Low displacement hazard: silty clay, clay, sandy clay, silty clay loam

Medium displacement hazard: silt, silt loam, loam, sandy clay loam, very fine sandy loam

High displacement hazard: sandy loam, loamy sand, sand, ashy loam, ashy silt loam, medial loam, medial silt loam

Ratings are reduced by one class, such as from "high" to "medium," if the surface layers with 1 percent or more percent organic matter are more than 6 inches thick. Ratings are reduced by one class for rock fragment content of 35 to 60 percent by volume and are reduced by two classes for rock fragment content of greater than 60 percent.

The ratings are both verbal and numerical. Rating class terms indicate the soil displacement hazard.

A "High" rating indicates that the soils can be readily displaced by equipment operations. They have little resistance to movement. Unless protective measures are implemented, detrimental displacement is probable.

A "Medium" rating indicates that the soils can be displaced by equipment operations but are intermediate in their resistance to movement.

A "Low" rating indicates that soils are resistant to displacement. Detrimental displacement is not likely to occur during equipment operations.

Numerical ratings indicate the soil displacement hazard. The ratings are shown in decimal fractions ranging from 1.00 to 0.00. They indicate gradations between the point where displacement hazard is highest (1.00) and the point at which displacement hazard is lowest (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is designed to predict the potential for soil puddling to occur from operation of ground-based equipment for forest harvesting and site preparation activities when soils have a moisture content that is at or above field capacity. Puddling is the loss of soil structure that results from squeezing and churning of soils by tires or tracks of heavy equipment. Soil particles become dispersed in water, and after they have dried and settled, the smaller particles form a crust on the surface. Soil puddling reduces porosity and increases bulk density by reducing the interaggregate pore space.

Puddled soils are less favorable for optimal plant growth because of high soil bulk density and hardness, reduced pore space, and poor aeration and drainage. Root penetration and growth are decreased in puddled soils because the hardness or strength of these soils prevents the expansion of roots. Supplies of air, water, and nutrients that roots need are also reduced when puddling decreases soil porosity and drainage.

Interpretation ratings are based on soil properties in the upper 12 inches of the profile. Factors considered are soil texture, soil structure, and rock fragment content. Initial ratings are based on the following soil texture groups:

Low puddling potential: loamy sand, loamy fine sand, loamy coarse sand, sand, fine sand, coarse sand, sandy loam with less than 15 percent clay

Medium puddling potential: loam, silt, silt loam with less than 15 percent clay, very fine sandy loam, sandy loam with 15 percent or more clay

High puddling potential: silty clay, clay, sandy clay, sandy clay loam, silty clay loam, clay loam, silt loam with 15 percent or more clay

Ratings are reduced by one class, such as from "high" to "medium," for strong soil structure grade. Ratings are reduced by one class for rock fragment content of 35 to 60 percent by volume and are reduced by two classes for rock fragment content of greater than 60 percent.

The ratings are both verbal and numerical. Rating class terms indicate the soil puddling potential.

A "Low" rating indicates that soils are resistant to puddling.

A "Medium" rating indicates that soils can be puddled by equipment operation, but the damage is often not extreme and mitigation measures are effective.

A "High" rating indicates that soils can be readily puddled by equipment operation. Mitigation of the damage is difficult.

Numerical ratings indicate the soil puddling potential. The ratings are shown in decimal fractions ranging from 1.00 to 0.00. They indicate gradations between the point where puddling potential is highest (1.00) and the point at which puddling potential is lowest (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings in this interpretation indicate the hazard of surface rut formation through the operation of forestland equipment. Soil displacement and puddling (soil deformation and compaction) may occur simultaneously with rutting.

Ratings are based on depth to a water table, rock fragments on or below the surface, the Unified classification of the soil, depth to a restrictive layer, and slope. The hazard is described as slight, moderate, or severe. A rating of "slight" indicates that the soil is subject to little or no rutting. "Moderate" indicates that rutting is likely. "Severe" indicates that ruts form readily.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Soil rutting occurs when the soil cannot support the weight of the machinery being driven across it. The degree of rutting depends upon the interaction of the contact pressure of the machine, the strength of the soil (as inferred by the AASHTO group index), and soil wetness. The soil interpretations for soil rutting hazard are used as a tool in timing heavy equipment use, evaluating soil suitability for traffic, and identifying soil limitations for operations.

The ratings in this interpretation indicate the hazard of surface rut formation through the operation of forestland equipment during the indicated month. Soil displacement and puddling (soil deformation and compaction) may occur simultaneously with rutting.

Rutting involves the displacement and movement of soil. It changes the structure of the soil and can adversely affect lateral flow of water through the landscape. Near-surface plant roots can also be damaged. Soil water content is a major factor in soil rutting because of the influence of water on the grain-to-grain cohesion of soil. The effect is most strongly pronounced in clayey soils. The deformation of soil under stress is a relatively complex process that depends on the amount and type of clay and the shapes of the various soil size separates. The process can be understood by application of the Atterberg limits. When the water content of a soil layer exceeds its plastic limit, application of a load will cause deformation. The water content at the plastic limit is generally less than the 1/3-bar water-holding capacity. It is important in timing heavy equipment usage during a rainy season, even if the soil is not saturated.

The AASHTO group index is a convenient way to rate the strength of soils because it accounts for both the fine-earth fraction of the soil and rock fragment content. The Group Index numbers are diagnostic in the range from 0 to 20; in terms of strength, soils with an index of 0 are not limited and soils with index 20 are very limited. Rock fragment content and bulk density have an effect on bearing capacity but are not considered individually in this rating.

Ratings are based on depth to a water table by month, since the depth to saturation of a soil can change monthly and it has a profound effect on soil strength. The soil conditions that affect rutting are evaluated for each month. The AASHTO group index and the depth to a restrictive layer are considered. A cemented layer close to the surface will limit the depth to which a tire or track can sink into the soil.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by the soil features that affect rutting. The hazard is described as slight, moderate, or severe. A rating of "Slight" indicates that the soil is subject to little or no rutting. "Moderate" indicates that rutting is likely. "Severe" indicates that ruts form readily.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.00 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Hambleton, J.P., and A. Drescher. 2009. Modeling wheel-induced rutting in soils: Rolling. Journal of Terramechanics 46(2):35, 47. Raper, R.L. 2005. Agricultural traffic impacts on soil. Journal of Terramechanics 42:259, 280.

Sutherland, B.J. 2003. Preventing Soil Compaction and Rutting in the Boreal Forest of Western Canada: A Practical Guide to Operating Timber-Harvesting Equipment. Forest Engineering Research Institute of Canada. Advantage Volume 4, No. 7.

Soil rutting occurs when the soil cannot support the weight of the machinery being driven across it. The degree of rutting depends upon the interaction of the contact pressure of the machine, the strength of the soil (as inferred by the AASHTO group index), and soil wetness. The soil interpretations for soil rutting hazard are used as a tool in timing heavy equipment use, evaluating soil suitability for traffic, and identifying soil limitations for operations.

The ratings in this interpretation indicate the hazard of surface rut formation through the operation of forestland equipment during the indicated season. Soil displacement and puddling (soil deformation and compaction) may occur simultaneously with rutting.

Rutting involves the displacement and movement of soil. It changes the structure of the soil and can adversely affect lateral flow of water through the landscape. Near-surface plant roots can also be damaged. Soil water content is a major factor in soil rutting because of the influence of water on the grain-to-grain cohesion of soil. The effect is most strongly pronounced in clayey soils. The deformation of soil under stress is a relatively complex process that depends on the amount and type of clay and the shapes of the various soil size separates. The process can be understood by application of the Atterberg limits. When the water content of a soil layer exceeds its plastic limit, application of a load will cause deformation. The water content at the plastic limit is generally less than the 1/3-bar water-holding capacity. It is important in timing heavy equipment usage during a rainy season, even if the soil is not saturated.

The AASHTO group index is a convenient way to rate the strength of soils because it accounts for both the fine-earth fraction of the soil and rock fragment content. The Group index numbers are diagnostic in the range from 0 to 20; in terms of strength, soils with an index of 0 are not limited and soils with index 20 are very limited. Rock fragment content and bulk density have an effect on bearing capacity but are not considered individually in this rating.

Ratings are based on depth to a water table by season, since the depth to saturation of a soil can be seasonal and it has a profound effect on soil strength. The soil conditions that affect rutting are evaluated for the spring (March, April, and May), summer (June, July, and August), fall (September, October, and November), and winter (December, January, and February). The AASHTO group index and the depth to a restrictive layer are considered. A cemented layer close to the surface will limit the depth to which a tire or track can sink into the soil.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by the soil features that affect rutting. The hazard is described as slight, moderate, or severe. A rating of "Slight" indicates that the soil is subject to little or no rutting. "Moderate" indicates that rutting is likely. "Severe" indicates that ruts form readily.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Hambleton, J.P., and A. Drescher. 2009. Modeling wheel-induced rutting in soils: Rolling. Journal of Terramechanics 46(2):35, 47. Raper, R.L. 2005. Agricultural traffic impacts on soil. Journal of Terramechanics 42:259, 280.

Sutherland, B.J. 2003. Preventing Soil Compaction and Rutting in the Boreal Forest of Western Canada: A Practical Guide to Operating Timber-Harvesting Equipment. Forest Engineering Research Institute of Canada. Advantage Volume 4, No. 7.

Ratings for this interpretation indicate the expected difficulty of hand planting of forestland plants. The ratings are based on slope, depth to a restrictive layer, content of sand, plasticity index, rock fragments on or below the surface, depth to a water table, and ponding. It is assumed that necessary site preparation is completed before seedlings are planted.

The ratings are both verbal and numerical. Rating class terms indicate the degree to which the soils are suited to this aspect of forestland management. "Well suited" indicates that the soil has features that are favorable for the specified management aspect and has no limitations. Good performance can be expected, and little or no maintenance is needed. "Moderately suited" indicates that the soil has features that are moderately favorable for the specified management aspect. One or more soil properties are less than desirable, and fair performance can be expected. Some maintenance is needed. "Poorly suited" indicates that the soil has one or more properties that are unfavorable for the specified management aspect. Overcoming the unfavorable properties requires special design, extra maintenance, and costly alteration. "Unsuited" indicates that the expected performance of the soil is unacceptable for the specified management aspect or that extreme measures are needed to overcome the undesirable soil properties.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation shows the suitability of soils for use as log landings in forested areas. Ratings are based on slope, rock fragments on the surface, plasticity index, content of sand, the Unified classification of the soil, depth to a water table, ponding, flooding, and the hazard of soil slippage.

The ratings are both verbal and numerical. Rating class terms indicate the degree to which the soils are suited to this aspect of forestland management. The soils are described as "well suited," "moderately suited," or "poorly suited" to use as log landings. "Well suited" indicates that the soil has features that are favorable for log landings and has no limitations. Good performance can be expected, and little or no maintenance is needed. "Moderately suited" indicates that the soil has features that are moderately favorable for log landings. One or more soil properties are less than desirable, and fair performance can be expected. Some maintenance is needed. "Poorly suited" indicates that the soil has one or more properties that are unfavorable for log landings. Overcoming the unfavorable properties requires special design, extra maintenance, and costly alteration.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings in this interpretation indicate the expected difficulty of planting trees or shrubs using a mechanical planter. The ratings are based on slope, depth to a restrictive layer, content of sand, plasticity index, rock fragments on or below the surface, depth to a water table, and ponding. It is assumed that necessary site preparation is completed before seedlings are planted.

The ratings are both verbal and numerical. Rating class terms indicate the degree to which the soils are suited to this aspect of forestland management. The soils are described as "well suited," "moderately suited," "poorly suited," or "unsuited" to this method of planting. "Well suited" indicates that the soil has features that are favorable for the specified management aspect and has no limitations. Good performance can be expected, and little or no maintenance is needed. "Moderately suited" indicates that the soil has features that are moderately favorable for the specified management aspect. One or more soil properties are less than desirable, and fair performance can be expected. Some maintenance is needed. "Poorly suited" indicates that the soil has one or more properties that are unfavorable for the specified management aspect. Overcoming the unfavorable properties requires special design, extra maintenance, and costly alteration. "Unsuited" indicates that the expected performance of the soil is unacceptable for the specified management aspect or that extreme measures are needed to overcome the undesirable soil properties.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the specified aspect of forestland management (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Windfirmness is the ability of a tree to resist overturning. It is a function of the balance between the anchorage or strength of the root/soil mass and the wind drag and gravitational forces applied on the tree crown. Windthrow is one type of wind damage. It is the uprooting of a tree by pivoting on the outer edge of a mass of soil, rock, and roots. Windthrow occurs when the horizontal forces on a tree (wind drag) are transmitted down the trunk and create a torque that exceeds the resistance to turning of the root and soil system (Stathers et al., 1994). The process varies depending on silvicultural practices, wind, tree species, site, and soil type. For example, individual tree characteristics contribute to windthrow. Trees with large, dense canopies are more susceptible to windthrow than those with open canopies. The strength and elasticity of the bole, branches, and leaves also contribute. The characteristics of the stand can influence the susceptibility to windthrow as well. Stand height and stand density are major factors; shorter and denser stands are more resistant to windthrow than tall, open stands. The rooting habits of the tree species impact the risk of windthrow; deeper-rooted trees are more resistant to the effects of wind than shallow-rooted species (Stathers et al., 1994). Soil and site factors are also important. According to most windthrow studies, the soil factors that control rooting depth contribute most significantly to the risk of windthrow. Rooting depth in soil can be restricted by a variety of features. Indurated, strongly cemented, and cemented layers, such as unweathered bedrock and duripans, are more or less root impenetrable. Some noncemented layers, such as fragipans, can also curtail root penetration. Persistent anoxic layers, such as a stagnant shallow water table, can act like an impervious layer. Wetness also has a deleterious effect on the shear strength of the soil, decreasing windfirmness. The weight of the soil over the roots adds a stabilizing anchoring influence. The shape of the land surface is also a factor in windthrow. While the effects are complex, the trees on certain exposed portions of the landscape are more subject to high windspeeds under most circumstances. Windspeed increases as wind streamlines are compressed by flowing through narrowing valleys, over hills and ridges, or around shoulder slopes. Wind direction is also a factor. In general, ridgetops, shoulder slopes, and backslopes tend to increase windspeed. This interpretation is intended to indicate those soil components on which the trees would be prone to windthrow.

The soil and site criteria that are considered in this soil interpretation are those that have the greatest effect on windthrow. They include the depth to a root-limiting layer, the position of the tree on the landscape, the shape of the landscape, and the cohesiveness of the soil in which the tree is rooted. Each soil and site criterion is assigned a numerical rating between 0 and 1. For this interpretation, a rating of 1 represents the least favorable soil and site characteristics and 0 represents the most favorable soil and site characteristics. Windthrow hazard is an indicator of the relative susceptibility of trees growing on a soil component to being blown over by wind. Soil and site factors, while important, are not the only factors that need to be considered in the process of windthrow. Silvicultural practices, tree species, and climatic variables are also involved.

Rating classes are defined as follows:

Severe (numerical rating of 1): Soils and sites where windthrow is likely to occur under conditions of high winds and decreased shear strength.

Moderate (numerical rating of 0.01 to 0.99): Soils and sites where windthrow may occur only under conditions of extreme windspeeds and decreased shear strength. Slight (numerical rating of 0): Soils and sites where windthrow may occur only under conditions of very extreme windspeeds and decreased shear strength.

Not Rated: Miscellaneous areas.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Reference:

Stathers, R.J., T.P. Rollerson, and S.J. Mitchell. 1994. Windthrow Handbook for British Columbia Forests. British Columbia Ministry of Forests, Victoria. Working Paper 9401.

Chaining is commonly practiced, sometimes in combination with seeding, during rangeland restoration. Chaining is implemented to reduce the composition of pinyon and juniper trees, mesquite, or sagebrush. Chaining also helps bury seed broadcast prior to chaining or between two chaining operations.

Chaining is often performed with an "Ely" chain or other similarly modified heavy chain dragged in a loose U-shaped or J-shaped pattern between two crawler tractors.

The chaining suitability ratings represent the relative physical limitations of soil factors upon use of implements suitable for chaining rangeland sites. This rating should be used in conjunction with the rangeland seeding rating or the restoration opportunity rating depending upon whether seeding or natural regeneration will be utilized on the site.

Steep slopes limit the ability to safely perform the chaining operation along the contour. Stones and rock outcrop potentially hinder the operation of the equipment. High water table affects the timing of tillage by limiting access to the site. On-site investigation is recommended before implementing any chaining projects.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for chaining. "Well suited" indicates that the soil has features that are very favorable for this use. Good performance can be expected. "Suited" indicates that the soil has features that are favorable for this use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance can be expected. "Poorly suited" indicates that the soil has one or more features that are unfavorable for this use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance can be expected.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of suitability of the soil for chaining. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

AGR - Agriculture

Livestock fencing is the construction and maintenance of barriers for the management of livestock. Fences are constructed using metal or wooden posts that are either treated or untreated to prevent rotting. The posts are buried at least two feet into the soil with strands of barbed or smooth wire or mesh wire suspended between the posts. It is desirable for livestock fence design to provide for wildlife movement. This guide is used to rate the ease of setting posts, maintaining the wire tension, and estimating the replacement and maintenance cost. Excavations for wooden posts are made by power auger or hand dug; metal posts are driven into the soil. Bedrock, cemented pan, and content of coarse fragments influence the excavation of post holes and the driving of posts. Flooding and depth to a seasonal high water table may restrict the season of construction. Flooding also affects maintenance and replacement cost. High water tables raise the maintenance cost and require deeper post settings. High shrink-swell soils require deep post settings or rock jacks to maintain vertical post alignment. Setting posts in permanently frozen soil may cause loss of the insulation qualities of the soil and result in thermokarst topography. Post alignment and maintaining the desired wire tension are often difficult on sandy soils due to their low strength. Soil blowing causes maintenance problems. Frost action results in frost-heaving of the posts. Steep slopes affect the use of power augers and the delivery of supplies. During wet seasons, surface creep on steep slopes increases maintenance. Soil reaction and salinity affect the type of post selected and maintenance costs.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for fences. "Well suited" indicates that the soil has features that are very favorable for this use. Good performance and low maintenance can be expected. "Moderately suited" indicates that the soil has features that are favorable for this use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Poorly suited" indicates that the soil has one or more features that are unfavorable for this use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

The overall rating class for each soil is assigned based on the average numerical rating of the individual soil properties considered in the interpretation, some of which may not displayed.

Numerical ratings indicate the level of suitability of the soil for fences. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Wildfire is a naturally occurring event that has helped maintain ecosystem function in wildlands. Wildfire can be caused by natural ignition such as lightning strike, or by man-caused ignition. Buildup of excess fuel loads can result in high severity fires that damage the soils in the burn area. Prescribed burning is a restoration practice that is primarily designed to help return the natural fire cycle to the landscape. Properly carried out on suitable sites, burning can be a very effective and cost efficient treatment method to help restore the desired composition of plant species in an ecological site, improve livestock access on heavy brush or slash sites, rejuvenate sprouting browse species and stagnant grass plants, release nutrients into the soil, improve palatability and nutrient content of forage, reduce fuel loading, and prepare an ash seedbed for artificial or natural seeding. Burning may be combined with mechanical or chemical rangeland treatments.

Fuel ignition for prescribed burning can be natural or artificial using hand-held drip torches, aerial ignition, and other methods. Fire lines can be established using natural fuel breaks, wet lines, or the removal of fuel by hand or machinery.

The susceptibility to fire damage ratings represent the relative risk of creating a water repellant layer, volatilization of essential soil nutrients, destruction of soil biological activity, and vulnerability to water and wind erosion prior to reestablishing adequate watershed cover on the burned site. The ratings are directly related to burn severity (e.g. a low-moderate severity burn will not result in water repellant layer formation). This rating should be used in conjunction with the rangeland seeding ratings or the soil restoration potential rating depending upon whether seeding or natural regeneration will be utilized on the site.

Sandy soils are more susceptible to formation of a water repellant layer. High rock fragment content increases the rate of heat transfer into the soil. Steep slopes increase the vulnerability to water erosion. Susceptibility to formation of hydrophobic or water repellant layers varies by vegetation type. As an example, pinyon-juniper, Arizona chaparral, and California chaparral vegetation types are more susceptible to hydrophobicity than other shrubland or grassland vegetation types.

The impacts of wildfire to soils of the burn area need to be assessed to prioritize burned area emergency rehabilitation and revegetation efforts.

Prescribed burning should be carefully planned and executed. It should be carried out following a well designed prescription and burn plan under the supervision of a qualified prescribed burning team. Burning objectives should be clearly defined and should be evaluated during post-burn assessments. Minimizing risks to human health, safety, and property damage and containment of the burn are of paramount importance.

Hot, dry south-facing slopes are more susceptible to fire damage than cooler, north-facing slopes. Fire mortality of desirable plants needs to be taken into consideration during wildfire restoration and prescribed burning planning. On-site investigation is recommended before implementing any wildfire restoration or prescribed burning projects.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect soil damage by fire. "Highly susceptible" indicates that the soil has one or more features that are very favorable for soil damage by fire. "Moderately susceptible" indicates that the soil has features that are moderately favorable for damage to occur. "Slightly susceptible" indicates that the soil has features that generally make it unfavorable for damage to occur.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest impact favoring soil damage by fire (1.00) and the point at which the soil feature is not favorable to damage occurring (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates the vulnerability of a soil for eroded soil particles to go into suspension during a windstorm. Fugitive dust can create extreme visibility reductions during severe windstorms creating traffic hazards and closing airports. Power outages, expensive cleanup costs, damage to computers and communications equipment from dust, transport of potentially harmful chemicals adhering to the soil particles, and loss of soil nutrients are some of the potential effects of fugitive dust. A positive impact is that nutrient enrichment can occur where fugitive dust is deposited.

Fugitive dust is a source of PM10 which is one of the seven air pollutants the Environmental Protection Agency regulates under the National Ambient Air Quality Standards (NAAQS). To a lesser extent, fugitive dust is a source of PM2.5 which has proposed regulations pending under NAAQS. PM10 and PM2.5 are defined as particulate matter with a mean diameter less than 10 microns and 2.5 microns respectively. These soil particles are very small, can remain suspended in the air for long periods of time, and are easily inhaled into the deep lungs. Increased risks of death and disease have been linked to periods of high outdoor PM10 and PM2.5 concentrations. These fine particles can potentially be lifted thousands of feet into the atmosphere and transported across continents and oceans creating global health, ecological, and climate change impacts.

The soil properties and qualities that affect fugitive dust are size of surface soil particles, rock fragment content, organic matter content, calcium carbonate equivalent, aggregate stability and presence of a stable soil crust. Clay particles have a strong propensity to form relatively large, durable soil aggregates and not contribute appreciably to fugitive dust unless these aggregates are broken down by intensive surface disturbance. Soil moisture and the presence of frozen soil also influence fugitive dust. Activities which break down soil aggregates and crusts increase wind erosion and production of fugitive dust.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which all of the soil features affect the formation of dust. "Low resistance" indicates that the soil has features that are very favorable for the formation of dust. "Moderate resistance" indicates that the soil has features that are favorable for dust formation. "High resistance" indicates that the soil has features that are unfavorable for dust formation.

Numerical ratings indicate the level of vulnerability of the soil for dust formation. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature resists dust formation (1.00) and the point at which the soil feature is favorable to the formation of dust (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its suitability for a rolling drum mechanical treatment which is commonly practiced, sometimes in combination with seeding, for rangeland restoration. It is implemented to reduce the size and composition of brush and young, smaller-sized trees, increase infiltration, and reduce runoff and erosion. The equipment may also help bury seed broadcast prior to or during treatment. The drums are often filled with water, or slurry made up of a mixture of water and soil, to increase drum weight and improve treatment effectiveness.

A rolling drum mechanical treatment is usually performed with a roller chopper, spiral-blade chopper, or land imprinter. Roller choppers utilize a cylindrical drum, equipped with several full-length cutting blades, that is towed behind a crawler-type tractor. Spiral-blade choppers use small blades welded to heavy drums in a staggered, spiral pattern around the drum. Land imprinters use a heavy drum with wedges to imprint small depressions into the soil and are mainly used for seedbed preparation.

The rolling drum mechanical treatment ratings represent the relative physical limitations of soil factors upon use of rolling drum implements suitable for treatment of rangeland sites. This rating should be used in conjunction with the rangeland seeding rating or the opportunity for restoration rating depending upon whether seeding or natural regeneration will be utilized on the site.

Steep slopes increase the power requirements for the equipment and limit the ability to safely perform the roller chopping operation. Stones and rock outcrop damage the blades of the roller chopper and make towing more difficult. High clay content reduces effectiveness of the treatment. High water table affects the timing of tillage by limiting access to the site. On-site investigation is recommended before implementing any rolling drum mechanical treatment projects.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for the use. 'Well suited' indicates that the soil has features that are very favorable for this use. Good performance can be expected. 'Moderately suited' indicates that the soil has features that are generally favorable for this use. Fair performance can be expected. 'Poorly suited' indicates that the soil has one or more features that are unfavorable for this use. Poor performance can be expected.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of suitability of the soil for rolling drum mechanical treatment. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its suitability for a shredder mechanical treatment which is commonly practiced, sometimes in combination with seeding, for rangeland restoration. The shredder mechanical treatment ratings represent the relative physical limitations of soil factors upon use of shredder implements suitable for treatment of rangeland sites. This rating should be used in conjunction with the rangeland seeding ratings or the soil restoration potential rating depending upon whether seeding or natural regeneration will be utilized on the site.

The shredder mechanical treatment is often implemented in sagebrush, mountain shrub, and pinyon-juniper vegetation types to reduce the size and composition of dense brush and trees up to 15-18 inches diameter, depending upon the equipment used. The treatment objectives can include reducing hazardous fuel loads, increasing forage for livestock and wildlife, increased infiltration, and reduced runoff and erosion. The equipment may also help bury seed broadcast prior to or during treatment.

There are several types of shredder equipment used for these treatments. One of the most commonly used is a large, articulated tractor with a front-mounted, 6-8 foot wide, hydraulically controlled mower/mulcher head. The machine has rubber, flotation-type tires which are designed for minimal ground disturbance. The mower/mulcher head is lifted above the tree or shrub top and lowered quickly, usually completely chopping the plant in less than 15 seconds. The rubber tired machine can also be equipped with flail shredders which use blades attached to a long, rotating horizontal shaft. The rotating drum can be 3 to 6 feet wide by 2 feet in diameter and is often mounted on the end of a boom. The most common type of rubber-tired shredder can safely operate on slopes up to about 20%. Tracked vehicles are also used which can be crawler tractors or excavators equipped with a flail type or mower/shredder type attachment to shred the shrubs or trees. Excavators have the shredder attachment mounted on a boom that can extend in any direction. The tracked shredders can operate on slopes up to 30-35%. Large pieces of debris can be thrown 200-300 feet during shredder operation, so safety to bystanders is an issue.

Steep slopes increase the power requirements for the equipment and limit the ability to safely perform the shredder operation. Stones and rock outcrop make equipment operation more difficult. High water table affects the timing of tillage by limiting access to the site. On-site investigation is recommended before implementing any shredder mechanical treatment projects.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for the use. 'Well suited' indicates that the soil has features that are very favorable for this use. Good performance can be expected. 'Moderately suited' indicates that the soil has features that are generally favorable for this use. Fair performance can be expected. 'Poorly suited' indicates that the soil has one or more features that are unfavorable for this use. Poor performance can be expected.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of suitability of the soil for shredder mechanical treatment. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The interpretation provides invasion susceptibility ratings and identifies the dominant soil and site characteristics that influence the susceptibility of the site to medusahead invasion. Medusahead or medusahead wild rye (Taeniatherum caput-medusae (L.) Nevski) is an introduced, cool-season annual grass that is a major concern to range ecologists, wildlife biologists, and the livestock industry in the western United States. It is an aggressive invader of disturbed or poor condition sagebrush ecological sites that can suppress desirable, native vegetation. Medusahead is unpalatable to livestock and most wildlife species, the seeds are not digestible by upland game birds and other bird species. The long barbed awns can cause injury to the eyes, noses, and mouths of grazing animals. Medusahead can increase wildfire incidence in some dwarf sagebrush communities. It is listed as a noxious weed in California, Colorado, Nevada, Oregon, and Utah.

The medusahead invasion vulnerability rating is general in nature. It is designed to be used in the planning process to identify areas with a low resistance to invasion by medusahead. This allows the user to plan and develop management practices that will reduce the probability of medusahead invasion.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are vulnerable to medusahead invasion due to all of the soil features that influence invasion. "Highly susceptible" indicates that the soil has one or more features that are very favorable for invasion to occur. "Moderately susceptible" indicates that the soil has features that are moderately favorable for invasion. "Slightly susceptible" indicates that the soil has features that generally make it unfavorable for invasion to occur.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the degree of an individual soil feature's influence on invasion. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest influence on promoting medusahead invasion (1.00) and the point at which the soil feature does not promote invasion (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is general in nature. It provides suitability ratings and identifies the soil and dominant plant composition characteristics that influence the potential of the site for providing habitat for pygmy rabbits. This information allows the user to plan and develop restoration efforts for pygmy rabbits.

Pygmy rabbits (Brachylagus idahoensis) are found in SE Washington, E Oregon, S Idaho, SW Montana, SW Wyoming, NE California, N Nevada, and W Utah. Though the historical population and range of the pygmy rabbit is unclear, evidence suggests it was significantly larger than at present. Habitat loss and fragmentation, agricultural land conversion, sagebrush burning, and hunting are the primary causes of this decline. The pygmy rabbit is a candidate species for listing by the US Fish and Wildlife Service as a threatened or endangered species. The Columbia Basin pygmy rabbit is currently on the Federal endangered species list.

Pygmy rabbits spend the majority of their lives within 30 meters of their burrows. They depend upon sagebrush for about 98% of their winter diet, and a high portion of their spring and summer diet. Their habitat is closely associated with dense, tall sagebrush stands. Unlike other rabbits, pygmy rabbits dig their own burrows so they require deep, loose soils with low rock content. Other soil features that affect habitat potential include depth to saturation, flooding, ponding, and slope.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability for pygmy rabbit habitat. Soils and the associated vegetation that are rated "high potential" have no restrictions and provide favorable potential habitat for pygmy rabbits. A "moderate potential" rating implies that the site provides moderately favorable potential habitat for pygmy rabbits. There are some restrictive soil or plant composition features that limit the suitability of the site. "Low potential" indicates that the site characteristics are such that they do not provide potential habitat for pygmy rabbits without considerable effort to artificially create sagebrush habitat outside its natural range of occurrence. Existing plant composition should be used in combination with the ratings to help determine current habitat conditions and restoration needs based on the requirements of the wildlife species for food and cover.

The overall rating class for each soil is assigned based on the average numerical rating of the individual soil properties considered in the interpretation, some of which may not displayed.

Numerical ratings indicate the level of suitability of the soil for pygmy rabbit habitat. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation provides a rating of each for its suitability for using a rangeland drill in a rangeland seeding operation. Rangeland drill seeding is commonly practiced, often in combination with vegetation control techniques to revegetate depleted rangeland. The rangeland drill was designed for treating rangeland by the Forest Service Equipment Development Center at San Dimas, California. It is a very heavy-duty, side-wheel drill featuring large wheels, a high-clearance reinforced frame, and single-disk openers that are independently suspended on trailing arms. The trailing arms have skid plates underneath to prevent breakage.

The rangeland drill suitability ratings represent the relative physical limitations of soil factors upon use of a rangeland drill. This rating should be used in conjunction with the rangeland seeding rating to ensure that the potential treatment areas would respond favorably to seeding. It is important to obtain the maximum benefit/cost ratio for expensive restoration/revegetation treatments.

Rock fragments and rock outcrop potentially damage the rangeland drill. Steep slopes limit the ability to safely operate a rangeland drill along the contour. High clay content reduces the effectiveness of the rangeland drill and ability to operate equipment during wet soil conditions. Too sandy surface textures reduce the effectiveness of the rangeland drill. Ponding, flooding, and high water table affect the timing of rangeland drill seeding by limiting access to the treatment area. On-sight investigation is recommended before implementing any rangeland drill seeding projects.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for the use. "Well suited" indicates that the soil has features that are very favorable for this use. Good performance can be expected. "Moderately suited" indicates that the soil has features that are favorable for this use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance can be expected. "Poorly suited" indicates that the soil has one or more features that are unfavorable for this use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance can be expected.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of suitability of the soil for use of the rangeland drill. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its suitability for rangeland seeding and establishing a successful seeding. Rangeland seeding is commonly practiced in combination with vegetation control techniques to revegetate depleted rangeland. Rangeland seeding may be accomplished using a rangeland drill, or broadcast seeding using aerial or ground equipment. Criteria used in this interpretation are applicable to the Colorado Plateau Ecoregion of Colorado, Utah, Arizona, and New Mexico.

Low precipitation, shallow rooting depth, abrupt textural boundary, excess salt, and excess sodium reduce the probability of establishing a successful seeding.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for rangeland seeding. "Well suited" indicates that the soil has features that are very favorable for this use and that a successful seeding can be expected in 8 or more years out of 10. A wide variety of grass, forb, and shrub species are well adapted to seeding on that site and a high potential forage production level can be anticipated. The benefit/cost ratios are favorable and these sites should be given primary consideration for rangeland restoration seeding.

"Moderately Suited" indicates that the soil has features that are favorable for this use and that a successful seeding can be anticipated in 6 or 7 years out of 10. A limited number of plant species are adapted to seeding on the site and a moderate potential forage production level can be achieved. Benefit/cost ratios are somewhat reduced, but may still be favorable. These soils should be given secondary consideration for rangeland restoration seeding.

"Poorly suited" indicates that the soil has one or more features that are unfavorable for this use and that a successful seeding can be expected in 4 or 5 years out of 10. Only a few plant species are adapted to seeding on these soils and a fairly low potential forage production level can be anticipated. Benefit/cost ratios will be poor. These sites have a low seeding potential, and it's recommended that they only be considered for restoration seeding if they occur in a mapping unit complex with more favorable soils. Emergency seeding after fire for erosion control may be justified though.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of suitability of the soil for chaining. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its suitability for rangeland seeding and establishing a successful seeding. Rangeland seeding is commonly practiced in combination with vegetation control techniques to revegetate depleted rangeland. Rangeland seeding may be accomplished using a rangeland drill, or broadcast seeding using aerial or ground equipment. Criteria used in this interpretation are applicable to the Great Basin Ecoregion of the Western U.S.

Low precipitation, shallow rooting depth, excess salt, and excess sodium reduce the probability of establishing a successful seeding.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for rangeland seeding. "Well suited" indicates that the soil has features that are very favorable for this use and that a successful seeding can be expected in 8 or more years out of 10. A wide variety of grass, forb, and shrub species are well adapted to seeding on that site and a high potential forage production level can be anticipated. The benefit/cost ratios are favorable and these sites should be given primary consideration for rangeland restoration seeding.

"Moderately Suited" indicates that the soil has features that are favorable for this use and that a successful seeding can be anticipated in 6 or 7 years out of 10. A limited number of plant species are adapted to seeding on the site and a moderate potential forage production level can be achieved. Benefit/cost ratios are somewhat reduced, but may still be favorable. These soils should be given secondary consideration for rangeland restoration seeding.

"Poorly suited" indicates that the soil has one or more features that are unfavorable for this use and that a successful seeding can be expected in 4 or 5 years out of 10. Only a few plant species are adapted to seeding on these soils and a fairly low potential forage production level can be anticipated. Benefit/cost ratios will be poor. These sites have a low seeding potential, and it's recommended that they only be considered for restoration seeding if they occur in a mapping unit complex with more favorable soils. Emergency seeding after fire for erosion control may be justified though.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of suitability of the soil for chaining. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its suitability for use of tillage equipment suitable for tilling rangeland ecological sites. Tillage is the use of mechanized equipment to disturb and to mix the soil usually to a depth of 3 to 12 inches from the surface. Rangeland tillage is commonly practiced in combination with seeding for rangeland restoration or revegetation. Plowing or discing is used to reduce the competition of sagebrush, and to a lesser extent, rabbitbrush, greasewood, and annual or perennial herbaceous plants that are considered undesirable. This treatment also helps remove compacted layers, improve soil tilth, and prepare a firm, friable seedbed for subsequent seeding operations.

Rangeland tillage is usually performed with a brushland plow; wheatland (one-way disc) plow; extra heavy-duty, offset disc; or chisel plow. The brushland plow's rugged construction and independently spring-loaded discs allow it to be used on rough, moderately stony or rocky sites without undue breakage. The wheatland plow is best suited to gentle slopes that are relatively free of stones and rock outcrop. The extra heavy-duty, offset disc is well adapted to use on compact, heavy textured soils. Chisel plows are used to control weeds, break up compacted soils, and increase water infiltration while leaving plant residue on the soil surface to reduce erosion. A wide variety of chisel points, sweeps, and shovels are available to accomplish desired tillage.

This rating should be used in conjunction with the rangeland seeding rating to ensure that the potential treatment areas would respond favorably to seeding. It is important to obtain the maximum benefit/cost ratio for expensive restoration/revegetation treatments.

Steep slopes limit the ability to safely operate these implements along the contour. Plowing up and down slope accelerates water erosion whereas plowing along the contour reduces water erosion. Sandy soils on gentle slopes susceptible to wind erosion should be plowed perpendicular to the prevailing wind direction. Depth to bedrock or cemented pan restricts the capability to do deep plowing. Stones and rock outcrop potentially damage and hinder the operation of the equipment. Ponding, flooding, and high water table affect the timing of tillage by limiting access to the site. High clay content reduces effectiveness of the tillage implements. On-sight investigation is recommended before implementing any rangeland tillage projects.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for the use. "Well suited" indicates that the soil has features that are very favorable for this use. Good performance can be expected. "Moderately suited" indicates that the soil has features that are favorable for this use. Fair performance can be expected. "Poorly suited" indicates that the soil has one or more features that are unfavorable for this use. Poor performance can be expected.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of suitability of the soil for tillage operations. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its susceptibility for soil degradation to occur during disturbance, which is a function of resistance to degradation. Resistance to degradation of a rangeland or woodland site is a measure of its ability to function without change throughout a disturbance. The magnitude of decline in the capacity to function determines the degree of resistance to change. Resistance to degradation thus could be described as an area's buffering capacity. This depends upon soil type, vegetation, climate, land use, disturbance regime, temporal and spatial scales. The disturbance regime determines the type of stresses placed upon the soil, vegetation, and wildlife components of the site. Thus, soil factors of vulnerability will vary based upon the disturbance regime for a particular site.

The ratings represent the relative risk of water and wind erosion, salinization, sodification, organic matter and nutrient depletion and/or redistribution, and loss of adequate rooting depth to maintain desired plant communities. Dynamic soil properties which vary with time, e.g. microbial biomass/diversity and carbon/nitrogen ratio, are not used since they are not contained within the soil database.

Steep slopes increase the potential for water erosion. Shallow rooting depth, and excess salt or sodium can reduce plant diversity, resistance to stress, and seedling survival.

This rating should be used with the objective to protect vulnerable sites from the type of degradation that would result in accelerated erosion, reduction in water and air quality, invasion by annual grasses or noxious weeds, and other large scale potential natural plant community conversions. When degradation of soil and natural plant community characteristics goes beyond the threshold for the ecological site, the ecological site characteristics cannot be restored without artificial restoration efforts.

There may be unique circumstances where accelerated soil processes that are normally considered contributing to site degradation are actually beneficial to some attribute of the site, such as Indian ricegrass (Achnatherum hymenoides) being more competitive in shifting sands than most species.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the potential for degradation. "Highly susceptible" indicates that the soil has one or more features that are very favorable for degradation. "Moderately susceptible" indicates that the soil has features that are moderately favorable for damage to occur. "Slightly susceptible" indicates that the soil has features that generally make it unfavorable for degradation to occur.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its resistance to compaction. Compaction tends to reduce water infiltration which affects plant production and composition, increases runoff which generally increased erosion rates, and affects organisms living within the soil.

Compaction is predominantly influenced by moisture content, depth to saturation, percent of sand, silt, and clay, soil structure, organic matter content, and content of coarse fragments.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for chaining. "High resistance" indicates that the soil has features that are very favorable to resisting compaction. "Moderate resistance" indicates that the soil has features that are favorable to resisting compaction. "Low resistance" indicates that the soil has one or more features that favor the formation of a compacted layer.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of the soil's resistance to compaction. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on resistance to compaction (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for its inherent ability to recover from degradation, which is often referred to as soil resilience. The ability to recover from degradation means the ability to restore functional and structural integrity after a disturbance. Both the rate and degree of recovery need to be considered. Soil functions that are important include sustaining biological activity, diversity and productivity; capture, storage and release of water; storing and cycling nutrients and other elements; filtering, buffering, degrading, immobilizing and detoxifying contaminants; providing support for plant and animal life; and protection for archeological sites. Restoration goals may include re-establishment of a preferred natural plant assemblage of the ecological site that existed prior to decline to a degraded state.

Soil resilience is dependent upon adequate stores of organic matter, good soil structure, low salt and sodium levels, adequate nutrient levels, microbial biomass and diversity, adequate precipitation for recovery, and other soil properties. Dynamic soil properties, such as microbial biomass and diversity or carbon nitrogen ratio, are not used for this rating since they are not contained within the soil database.

This rating should be used to help prioritize areas for restoration projects, such as prescribed burning, chaining, or herbicide application, that depend upon natural vegetation recovery. On-site investigation is recommended before undertaking any restoration project.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the soil's ability to recover. "High potential" indicates that the soil has features that are very favorable for recovery. Good performance can be expected. "Moderate potential" indicates that the soil has features that are generally favorable for recovery. Fair performance can be expected. "Low potential" indicates that the soil has one or more features that are unfavorable for recovery. Poor performance can be expected.

The overall rating class for each soil is assigned based on the product of the numerical ratings of the individual soil properties considered in the interpretation, some of which may not be displayed.

Numerical ratings indicate the level of for the soil to recover from degradation. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on recovery (1.00), and the point at which the soil feature has the greatest negative impact (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation rates each soil for it susceptibility for an invasion of yellow star-thistle to occur. The ratings are general in nature, and are designed to be used in the planning process to identify areas with a high vulnerability to invasion by yellow star-thistle. This allows the user to plan and develop management practices that will reduce the probability of yellow star-thistle invasion.

Yellow star-thistle (Centaurea solstitialis L) is an introduced, winter annual forb that is a major concern to range ecologists, wildlife biologists, recreationists, and the livestock industry. It is an aggressive invader of disturbed or poor condition rangeland sites that can suppress desirable, native vegetation. Yellow star-thistle has low palatability and nutritional value for livestock and most wildlife species, is toxic to horses, and it can increase wildfire incidence in some dwarf sagebrush communities. The seed is eaten by several species of birds. The plant it is considered an important honey source plant in California and other western states. Yellow star-thistle is listed as a noxious weed in Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, South Dakota, Utah, and Washington.

The interpretations provide invasion vulnerability ratings and identify the dominant soil and site characteristics that influence the susceptibility of the site to yellow star-thistle invasion.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect soil invasion by yellow star-thistle. A rating of "highly susceptible" indicates the soils have a high susceptibility to yellow star-thistle invasion. A "moderately susceptible" rating indicates that the site is moderately susceptible to yellow star-thistle invasion. A "slightly susceptible" rating indicates that the soil characteristics may limit establishment of yellow star-thistle invasions. Other factors, such as proximity to a seed source, also need to be considered in determining susceptibility to yellow star-thistle invasion.

The overall rating class for each soil is assigned based on the average numerical rating of the individual soil properties considered in the interpretation, some of which may not displayed.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest impact favoring invasion by yellow star-thistle (1.00) and the point at which the soil feature is unfavorable to an invasion (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

TROP - Cacao Suitability

The Cacao Suitability model is a method of arraying the soils of Puerto Rico, US Virgin Islands, and Hawaii for non-irrigated cacao suitability based on their inherent soil properties. The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Background

Cacao (Theobroma cacao) is a very important tropical crop. While cacao is very popular, with 5.9 million metric tons produced in 2022 globally, production is often difficult because it is typically grown on hilly terrain and it is labor intensive. Cacao plants require a mean annual temperature of 24 degrees C or higher and over 1300 mm of rainfall for optimum growth. They are adapted to a wide range of soils but do best on deep, well drained soils high in organic matter, water holding capacity, and not affected by salinity or excessive aluminum toxicity. Other soil and site properties, such as slope, available water storage, cation exchange capacity, water and gas transmission, soil depth, and the depth and timing of saturation are also known to affect the suitability of a site.

Ratings

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of cacao crops are major considerations. Soil suitability is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a moderately acid to near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. For the cacao crop suitability index, the site starts to become limiting at slopes exceeding 25 percent. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent suitability for cacao. The further a soil differs from ideality in any one or all of the factors that determine inherent suitability the lower its inherent suitability will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated suitability which is determined by all of the soil, site, and climatic features that affect suitability. "Well suited" indicates that the soil, site, and climate have features that are very favorable for crop production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Suited" indicates that the soil has features that are generally quite favorable for crop production. Good yields and moderately low risk of crop failure can be expected. "Somewhat suited" indicates that some but not all site and soil features are generally favorable for crop production. Moderate yields and moderate risk of crop failure can be expected. "Poorly suited" indicates that the soil has features that are generally not favorable for crop production. Low yields and moderately high risk of crop failure can be expected. "Not suited" indicates that the soil has one or more features that are unfavorable for crop production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Buggenhout, Erika. 2018. Assessment of soil quality for organic cocoa cultivation in southern Sao Tome. M.S. Thesis. University of Ghent.

Libohova, Z., J.M. Martín-López, M. da Silva, C. Lagoueyte, J. Cruz, P. Drohan, S. Maximova, M. Guiltinan, M.G. Ferruzzi, D. Guarín, P. Reich, C. Kome, Y.P. Zapata, G. Gallego-Sánchez, C. Quintero, C. Botero, N.P. Winters, and M. Robotham. 2020. Soil and cacao genomics survey of Sierra Nevada de Santa Marta Region, Colombia. United States Department of Agriculture, Natural Resources Conservation Service; International Center for Tropical Agriculture (CIAT); and Pennsylvania State University.

Augustine Prosper Osei-Gyabaah, Mary Antwi, Solomon Addo, Paul Osei. 2023. Land suitability analysis for cocoa (Theobroma cacao) production in the Sunyani municipality, Bono region, Ghana. Smart Agricultural Technology. Volume 5, 100262.

Sanchez, Pedro A. 2019. Properties and Management of Soils in the Tropics (2nd ed). Cambridge University Press. https://doi.org/10.1017/9781316809785.

TROP - Coffee (Arabica) Suitability

The Coffee Suitability model is a method of arraying the soils of Puerto Rico, US Virgin Islands, and Hawaii for non-irrigated coffee suitability based on their inherent soil properties. The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Background

Coffee is a tropical crop in the genus Coffee. Two main species are grown, Coffee arabica (Arabica) and Coffee canephora (Robusta). The model developed here is for the Arabica species. While coffee is very popular, with 3 billion cups consumed per day globally, production is often difficult because it is typically grown on hilly terrain and it is labor intensive (ICO, 2024). Coffee plants require a mean annual temperature of 18 to 24 degrees C and over 1300 mm of rainfall for optimum growth. They are adapted to a wide range of soils but do best on deep, well drained soils high in organic matter, water holding capacity, and not affected by salinity or excessive aluminum toxicity. Other soil and site properties, such as slope, available water storage, cation exchange capacity, water and gas transmission, soil depth, and the depth and timing of saturation are also known to affect the suitability of a site.

Ratings

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of coffee crops are major considerations. Soil suitability is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a moderately acid to near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. For the coffee crop suitability index, the site starts to become limiting at slopes exceeding 20 percent. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent suitability for coffee. The further a soil differs from ideality in any one or all of the factors that determine inherent suitability the lower its inherent suitability will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated suitability which is determined by all of the soil, site, and climatic features that affect suitability. "Well suited" indicates that the soil, site, and climate have features that are very favorable for crop production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Suited" indicates that the soil has features that are generally quite favorable for crop production. Good yields and moderately low risk of crop failure can be expected. "Somewhat suited" indicates that some but not all site and soil features are generally favorable for crop production. Moderate yields and moderate risk of crop failure can be expected. "Poorly suited" indicates that the soil has features that are generally not favorable for crop production. Low yields and moderately high risk of crop failure can be expected. "Not suited" indicates that the soil has one or more features that are unfavorable for crop production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Bittenbender, H. C. and V. E. Smith. 2008. Growing coffee in Hawaii. College of Tropical Agriculture and Human Resources. University of Hawai'i at Manoa.

Clifford, M.N. and Willson, K.C. (Editors). 1985. - Coffee; botany, biochemistry and production of beans and beverage. London, Croom Helm.

Daviron, Benoit, Stefano Ponte. 2005. The Coffee Paradox: Global Markets, Commodity Trade and the Elusive Promise of Development. Zed Books London and New York. ISBN 978-1-84277-457-1.

International Coffee Organization. 2024. Sustainability & Resilience of the Coffee Global Value Chain: Towards a Coffee Investment Vehicle. United Nations Industrial Development Organization. https://www.icocoffee.org/documents/cy2023-24/report-global-coffee-funding-mechanisms-june-2024-e.pdf?mc_cid=9fdadf1231&mc_eid=1f37b4a18b.

Sanchez, Pedro A. 2019. Properties and Management of Soils in the Tropics (2nd ed). Cambridge University Press. https://doi.org/10.1017/9781316809785.

TROP - Guineagrass Suitability

The Guineagrass Suitability model is a method of arraying the soils of Puerto Rico, US Virgin Islands, and Hawaii for non-irrigated guineagrass crop suitability based on their inherent soil properties. The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Background

Guineagrass (Megathyrsus maximus) is a tropical forage crop. While it is a valued forage crop, it is also highly invasive. It grows vigorously and must be managed carefully to avoid fires in dry weather. Guineagrass grows best at a mean annual temperature of 24 to 26 degrees C and over 1800 mm of rainfall for optimum growth, although it can tolerate some frost. It is adapted to a wide range of soils but does best on deep, well drained soils high in organic matter, water holding capacity, and not affected by salinity or excessive aluminum toxicity. Other soil and site properties, such as slope, available water storage, cation exchange capacity, water and gas transmission, soil depth, and the depth and timing of saturation are also known to affect the suitability of a site.

Ratings

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of guineagrass are major considerations. Soil suitability is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a moderately acid to near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. For the guineagrass suitability model, the site starts to become limiting at slopes exceeding 10 percent. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent suitability for guineagrass. The further a soil differs from ideality in any one or all of the factors that determine inherent suitability the lower its inherent suitability will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated suitability which is determined by all of the soil, site, and climatic features that affect suitability. "Well suited" indicates that the soil, site, and climate have features that are very favorable for crop production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Suited" indicates that the soil has features that are generally quite favorable for crop production. Good yields and moderately low risk of crop failure can be expected. "Somewhat suited" indicates that some but not all site and soil features are generally favorable for crop production. Moderate yields and moderate risk of crop failure can be expected. "Poorly suited" indicates that the soil has features that are generally not favorable for crop production. Low yields and moderately high risk of crop failure can be expected. "Not suited" indicates that the soil has one or more features that are unfavorable for crop production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall suitability of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Rhodes AC, Plowes RM, Martins DJ, Ng'Iru I, Gilbert LE (2022) The invasiveness of Guinea grass (Megathyrsus maximus) is characterized by habitat and differing herbivore assemblages in its native and invaded range. NeoBiota 78: 25, 44. https://doi.org/10.3897/neobiota.78.87069.

Rhodes, A. C., Robert M. Plowes, John A. Goolsby, John F. Gaskin, Boaz Musyoka, Paul-Andre´ Calatayud, Massimo Cristofaro, Eric D. Grahmann, Dino J. Martins, Lawrence E. Gilbert. 2021. The dilemma of Guinea grass (Megathyrsus maximus): a valued pasture grass and a highly invasive species. Biol Invasions (2021) 23:3653, 3669. https://doi.org/10.1007/s10530-021-02607-3.

Sanchez, Pedro A. 2019. Properties and Management of Soils in the Tropics (2nd ed). Cambridge University Press. https://doi.org/10.1017/9781316809785.

NCCPI - National Commodity Crop Productivity Index

National Commodity Crop Productivity Index is a method of arraying the soils of the United States for non-irrigated commodity crop production based on their inherent soil properties. This version features a separate index for soybeans. In the past, soybeans and corn were considered together. The rating a soil is assigned is the highest one of four basic crop group indices, which are based on the climate where the crop is typically grown. Cooler climates are represented by winter wheat, moderate climates are represented by corn and soybeans, and warmer climates are represented by cotton. (http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050734.pdf)

The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of crops are major considerations. Soil productivity is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent productivity for a particular crop. The further a soil differs from ideality in any one or all of the factors that determine inherent productivity, the lower its inherent productivity will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated productivity which is determined by all of the soil, site, and climatic features that affect crop productivity. "High inherent productivity" indicates that the soil, site, and climate have features that are very favorable for crop production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Moderately high inherent productivity" indicates that the soil has features that are generally quite favorable for crop production. Good yields and moderately low risk of crop failure can be expected. "Moderate inherent productivity" indicates that the soil has features that are generally favorable for crop production. Good yields and moderate risk of crop failure can be expected. "Moderately low inherent productivity" indicates that the soil has features that are generally not favorable for crop production. Low yields and moderately high risk of crop failure can be expected. "Low inherent productivity" indicates that the soil has one or more features that are unfavorable for crop production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

NCCPI - National Commodity Crop Productivity Index

NCCPI - NCCPI Corn Productivity is a method of arraying the soils of the United States for non-irrigated corn for grain productivity based on their inherent soil properties. For more information, see (http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050734.pdf)

The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of corn are major considerations. Soil productivity is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent productivity for a particular crop. The further a soil differs from ideality in any one or all of the factors that determine inherent productivity, the lower its inherent productivity will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated productivity which is determined by all of the soil, site, and climatic features that affect crop productivity. "High inherent productivity" indicates that the soil, site, and climate have features that are very favorable for corn production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Moderately high inherent productivity" indicates that the soil has features that are generally quite favorable for corn production. Good yields and moderately low risk of crop failure can be expected. "Moderate inherent productivity" indicates that the soil has features that are generally favorable for corn production. Good yields and moderate risk of crop failure can be expected. "Moderately low inherent productivity" indicates that the soil has features that are generally not favorable for corn production. Low yields and moderately high risk of crop failure can be expected. "Low inherent productivity" indicates that the soil has one or more features that are unfavorable for corn production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

NCCPI - National Commodity Crop Productivity Index

NCCPI - NCCPI Cotton Productivity is a method of arraying the soils of the United States for non-irrigated cotton for lint productivity based on their inherent soil properties. For more information, see (http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050734.pdf)

The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of small grains are major considerations. Soil productivity is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent productivity for a particular crop. The further a soil differs from ideality in any one or all of the factors that determine inherent productivity, the lower its inherent productivity will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated productivity which is determined by all of the soil, site, and climatic features that affect crop productivity. "High inherent productivity" indicates that the soil, site, and climate have features that are very favorable for cotton production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Moderately high inherent productivity" indicates that the soil has features that are generally quite favorable for cotton production. Good yields and moderately low risk of crop failure can be expected. "Moderate inherent productivity" indicates that the soil has features that are generally favorable for cotton production. Good yields and moderate risk of crop failure can be expected. "Moderately low inherent productivity" indicates that the soil has features that are generally not favorable for cotton production. Low yields and moderately high risk of crop failure can be expected. "Low inherent productivity" indicates that the soil has one or more features that are unfavorable for cotton production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

NCCPI - National Commodity Crop Productivity Index

NCCPI - NCCPI Small Grains Productivity is a method of arraying the soils of the United States for non-irrigated small grain productivity based on their inherent soil properties. The particular crop modeled is winter wheat. More specific models are pending. For more information, see (http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050734.pdf)

The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of small grains are major considerations. Soil productivity is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent productivity for a particular crop. The further a soil differs from ideality in any one or all of the factors that determine inherent productivity, the lower its inherent productivity will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated productivity which is determined by all of the soil, site, and climatic features that affect crop productivity. "High inherent productivity" indicates that the soil, site, and climate have features that are very favorable for small grains production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Moderately high inherent productivity" indicates that the soil has features that are generally quite favorable for small grains production. Good yields and moderately low risk of crop failure can be expected. "Moderate inherent productivity" indicates that the soil has features that are generally favorable for small grains production. Good yields and moderate risk of crop failure can be expected. "Moderately low inherent productivity" indicates that the soil has features that are generally not favorable for small grains production. Low yields and moderately high risk of crop failure can be expected. "Low inherent productivity" indicates that the soil has one or more features that are unfavorable for small grains production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

NCCPI - National Commodity Crop Productivity Index

NCCPI - NCCPI Soybeans Submodel (I) is a method of arraying the soils of the United States for non-irrigated soybean productivity based on their inherent soil properties. For more information, see (http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050734.pdf)

The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of soybeans are major considerations. Soil productivity is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent productivity for a particular crop. The further a soil differs from ideality in any one or all of the factors that determine inherent productivity, the lower its inherent productivity will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated productivity which is determined by all of the soil, site, and climatic features that affect crop productivity. "High inherent productivity" indicates that the soil, site, and climate have features that are very favorable for soybeans production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Moderately high inherent productivity" indicates that the soil has features that are generally quite favorable for soybeans production. Good yields and moderately low risk of crop failure can be expected. "Moderate inherent productivity" indicates that the soil has features that are generally favorable for soybeans production. Good yields and moderate risk of crop failure can be expected. "Moderately low inherent productivity" indicates that the soil has features that are generally not favorable for soybeans production. Low yields and moderately high risk of crop failure can be expected. "Low inherent productivity" indicates that the soil has one or more features that are unfavorable for soybeans production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings for Pesticide Loss Potential-Leaching are used for evaluating and determining the potential of the soil to transmit pesticides through the profile and the likelihood of the contamination of ground-water supplies. Evaluations consider movement of water through the soil and underlying fractured bedrock. Ratings are for soils in their natural condition and do not consider present land use. The properties that affect the pesticide loss potential include the soil's hydrologic group, depth to water table, saturated hydraulic conductivity at different depths, and the possibility of water movement in fractured bedrock. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that have low leaching potential. "Somewhat limited" indicates that the soil has features that are moderately rated for leaching potential. Some leaching can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable and leaching potential is high. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating. A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The ratings for Pesticide Loss Potential-Soil Surface Runoff are used for evaluating and determining the potential of the soil to transmit pesticides through surface runoff and the likelihood of the contamination of surface waters. Ratings are for soils in their natural condition and do not consider present land use. The properties that affect the pesticide loss potential include the occurrence of permafrost, surface ponding, flooding, and slope. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that have low runoff potential. "Somewhat limited" indicates that the soil has features that are moderately rated for runoff potential. Some runoff can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable and surface runoff is high. Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating. A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

TROP - Plantains Productivity Index

The Plantains Crop Productivity Index is a method of arraying the soils of Puerto Rico and US Virgin Islands for non-irrigated plantains crop production based on their inherent soil properties. The interpretation is applicable to both heavily populated and sparsely populated areas. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Background

Plantains and bananas are the fourth most important global food commodity (UNCST, 2007). Plantains (Musa spp. AAB) are similar to the dessert banana but are generally cooked before being eaten. Plantains are a critical staple crop in the tropics (Norgrove and Hauser, 2014). Plantains are the largest herbaceous plant and the pseudostem can be as tall as a tree between 2 and 8 meters tall. The pseudostem consists of compacted leaf sheaths, thus the plant does not have a woody stem (Karamura and Karamura, 1995). Plantains require a mean monthly temperature of 27 degrees C and evenly distributed rainfall for optimum growth. They are adapted to a wide range of soils but do best on deep, well drained soils high in organic matter, water holding capacity, and not affected by salinity or aluminum toxicity (Purseglove, 1972). Ssali (1972) determined that most of the root uptake occurred in the upper 60 cm of soil, which has implications for rooting and depth to saturation requirements. Other soil and site properties, such as slope, available water storage, cation exchange capacity, water and gas transmission, soil depth, and the depth and timing of saturation are also known to affect productivity.

Ratings

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 feet). Soil, site, and climate properties that influence the growth of plantain crops are major considerations. Soil productivity is influenced by many soil properties. An ideal soil will store adequate amounts of water to nurture the crop between rains. This soil will have a moderately acid to near-neutral pH, will store nutrients, and lack toxic materials. The soil will have no barriers, either physical or chemical, to root growth. Water and gas transmission through the soil will be sufficient to maintain both water and oxygen at sufficient levels in the root zone. The soil will not be saturated with water during the growing season to the point that root growth is inhibited. The soil will not be subject to excessive flooding or ponding during the growing season. Slope is an important consideration because it affects erosion by water, runoff, and the operation of equipment. For the plantain crop productivity index soil starts to become limiting at slopes exceeding 20 percent. The climate must provide adequate water and heat to allow the desired crop to mature. A soil that differs from the ideal in any of these features will have lower inherent productivity for a particular crop. The further a soil differs from ideality in any one or all of the factors that determine inherent productivity, the lower its inherent productivity will be.

The ratings are both verbal and numerical. Rating class terms indicate the estimated productivity which is determined by all of the soil, site, and climatic features that affect crop productivity. "High inherent productivity" indicates that the soil, site, and climate have features that are very favorable for crop production. High yields and low risk of crop failure can be expected if a high level of management is employed. "Moderately high inherent productivity" indicates that the soil has features that are generally quite favorable for crop production. Good yields and moderately low risk of crop failure can be expected. "Moderate inherent productivity" indicates that the soil has features that are generally favorable for crop production. Good yields and moderate risk of crop failure can be expected. "Moderately low inherent productivity" indicates that the soil has features that are generally not favorable for crop production. Low yields and moderately high risk of crop failure can be expected. "Low inherent productivity" indicates that the soil has one or more features that are unfavorable for crop production. Low yields and high risk of crop failure can be expected.

Numerical ratings indicate the overall productivity of the soil. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which the combination of soil, site, and climate features has the greatest positive impact on inherent productivity (1.00) and the point at which the soil features are very unfavorable (0.01).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Hernandez Ayala, J.J. 2012. Spatial and Temporal Changes in Precipitation in Puerto Rico from 1956-2010. Masters Thesis. Sonoma State University. https://www.researchgate.net/publication/262525155_Spatial_and_Temporal_Changes_in_Precipitation_in_Puerto_Rico_from_1956-2010.

Irizarry, H., E. Rivera, A. D. Krikorian, J. A. Rodríguez. 1991. Proper bunch management of the French-type superplantain (Musa acuminata x M. balbisiana, AAB) in Puerto Rico. The Journal of Agriculture of the University of Puerto Rico, 75(2), 163, 171. https://doi.org/10.46429/jaupr.v75i2.3579.

Karamura, E.B., and D.A. Karamura. 1995. Banana morphology, part II: The aerial shoot. Pp. 190-205. IN S. Gowen, ed., Bananas and Plantains. Chapman & Hall, London, UK.

Kottek, M., J. Griser, C. Beck, B. Rudolf, F. Rubel. 2006. World Map of the Köppen-Geiger climate classification updated. Meteorologische Zeitschrift, Vol. 15, No. 3, 259-263. DOI: 10.1127/0941-2948/2006/0130.

Norgrove, L., S. Hauser. 2014. Improving plantain (Musa spp. AAB) yields on smallholder farms in West and Central Africa. Food Sec. 6:501, 514. DOI 10.1007/s12571-014-0365-1.

OECD. 2010. Section 2 - Bananas and plantains (Musa spp.). Part 1. Consensus documents on the biology of crops. IN Safety assessment of transgenic organisms: OECD consensus documents: Volume 4. doi:https://doi.org/10.1787/9789264096158-6-en.

Purseglove, J.W. (1972) Tropical crops, Monocotyledons, Vol.2. Longmans, London.

Sotomayor-Ramírez, D. and G. Martínez. 2019. Chapter 1, Nutrient management for sustainable agriculture in the Caribbean. p. 1-1 to 1-15. In. Fertilizer Recommendations Guide for Some of the Most Common Crops in the Caribbean. Final Project Report under Cooperative Agreement no. 68-F352-16-501 between National Cooperative Soil Survey and Univ. of Puerto Rico Mayagüez.

Ssali, H., 1972. Determination of root activity of Bananas (Nakyetengu cultivar of the cooking type) during the wet and dry season as measured by radioactive phosphorus (32P) uptake. MSc. Thesis, Makerere University, Kampala.

Uganda National Council for Science and Technology (UNCST). 2007. The biology of bananas and plantains.

Soil Suitability for Industrial Hemp for Fiber and Seed

Industrial hemp produced for fiber and seed is seeing a resurgence in interest from farmers in many states. Although commonly cultivated in the United States prior to the 1940s, it fell out of vogue with the advent of other materials for producing rope and textiles. Industrial hemp is a non-drug variety of Cannabis sativa which has very low levels (less than 0.3%) of the psychoactive compound, tetrahydracannabinal (THC). It is a highly productive plant which can grow in a variety of climate and soil conditions. Any machinery that is easily adjustable, such as row widths, and performs well is suitable for sowing industrial hemp. Standard grain drills and modified alfalfa seeders are examples of suitable machinery. Ease of converting farm equipment to sow seeds makes this an appealing alternative. Ideally, industrial hemp should be incorporated into a four-year crop rotation. Industrial hemp does require an adequate amount of nutrients. Major nutrients include but, not limited to: (1) nitrogen, (2) potassium, and (3) phosphorus. Industrial hemp's dense canopy makes for effective weed suppression.

Industrial hemp requires certain soil and site characteristics for optimum growth. Slope, soil drainage, depth to a restrictive layer, frost-free days, ponding, flooding, rock fragment cover, and rock fragment content are important characteristics that are not easily altered. If any one of these attributes is unsuited for growing a crop, then the site is not suited. Other soil characteristics, such as available water storage, organic matter content, pH, electrical conductivity, cation exchange capacity, and hydraulic conductivity, while important, will generally not render a soil unsuited if one or two of these characteristics is sub-optimal. Also, these characteristics can be made more suitable when the soil is managed for optimal Soil Quality.

Two things need to be remembered about the "Industrial Hemp for Fiber and Seed Production" model. First, it is important to consider that this interpretation describes the suitability of a soil and site for industrial hemp production and does not necessarily imply a predicted yield, although better suited soils may be more productive. Second, the model assumes that if the crop needs to be irrigated due to insufficient precipitation, then water at appropriate levels will be applied. European studies show that industrial hemp requires 500 to 700 mm of moisture for optimum yield. Thus, annual precipitation will need to be higher than that range, depending on the soil and evapotranspiration. Research in the Midwest suggests 600 to 800mm of annual precipitation is needed.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are suited by all of the soil features that affect these uses. Numerical ratings indicate the degree of suitability of each soil or site feature. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest degree of suitability for the use (1.00) and the point at which the soil feature is not suited for the use (0.00).

Verbal ratings are defined as follows:

Well suited (rating index equals 1.0)., The soil and site properties present are optimal for the growth of hemp for seed and fiber.

Suited (rating index is greater than 0.75 but less than 1.0)., The soil and site properties are generally suited, but not optimal. The site may be sloping, have seasonal saturation, or have soil chemical or physical properties that may slightly limit the growth of hemp.

Moderately suited (rating index is greater than 0.25 but less than 0.75)., The soil and site properties are generally suited, but not well suited. The site may be sloping, have seasonal saturation, or have soil chemical or physical properties that may limit the growth of hemp. The crop will grow and produce on these sites, but harvest may be more difficult if the soil is sloping.

Poorly suited (rating index is greater than 0 but less than 0.25)., The suitability of the site is marginal for the management and production of the crop. While hemp will grow and produce a crop, it may not be of an economic quantity.

Not suited (rating index equals 0)., The soil is rendered unsuitable for hemp production due to very unfavorable conditions, such as excessive slope, severe wetness, or poor physical and chemical soil properties.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References and Resources

Amaducci, S., D Scordia, FH Liu, Q Zhang, H Guo, G Testa, SL Cosentino. 2015. Key cultivation techniques for hemp in Europe and China. Industrial Crops and Products 68, 2-16.

Bocsa, I. and Karus, M., 1998. The cultivation of hemp: botany, varieties, cultivation and harvesting. Hemptech.

Cherney, J.H.; Small, E. Industrial Hemp in North America: Production, Politics and Potential. Agronomy 2016, 6, 58. Cosentino, S. L., Testa, G., Scordia, D., & Copani, V, 2011. Sowing time and prediction of flowering of different hemp (Cannabis sativa L.) genotypes in southern Europe. Industrial Crops and Products, Volume 37, Issue 1.

Dewey, Lyster H. The Cultivation of Hemp in the United States. Bur. of Plant Industry Circular No. 57. (May 23, 1910).

Feasibility of industrial hemp production in the United States Pacific Northwest. Oregon State University Extension Service Station Bulletin 681, May 1998.

Fike, J. (2016) Industrial Hemp: Renewed Opportunities for an Ancient Crop, Critical Reviews in Plant Sciences, 35:5-6, 406-424, DOI: 10.1080/07352689.2016.1257842.

Industrial Hemp Production, Manitoba, CA. https://www.gov.mb.ca/agriculture/crops/production/hemp-production.html#field.

Jones, VD Jeliazkov, RJ Roseberg, SD Angima. 2019. Basics of Fall Cover Cropping for Hemp in Oregon, Oregon State University Extension Service. https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9255.pdf

Kaiser, C., Cassady, C., and M Ernst. 2015. Industrial Hemp Production. Center for Crop Diversification, Cooperative Extension Service, University of Kentucky.

Kraenzel, D. G., Petry, T., Nelson, B., Anderson, M. J., Mathern, D., & Tod, R. (1998, July 23). https://ageconsearch.umn.edu/record/23264. Retrieved February 28, 2020, from Moebius-Clune, B.N., D.J. Moebius-Clune, B.K. Gugino, O.J. Idowu, R.R. Schindelbeck, A.J. Ristow, H.M. van Es, J.E. Thies, H.A. Shayler, M.B. McBride, K.S.M Kurtz, D.W. Wolfe, and G.S. Abawi, 2016. Comprehensive Assessment of Soil Quality The Cornell Framework, Edition 3.2, Cornell University, Geneva, NY. http://www.css.cornell.edu/extension/soil-health/manual.pdf.

Nelson, R.A., 1999. Hemp Husbandry. Rex Research Archives.

Purdue University, Hemp Project, Hemp Production. https://purduehemp.org/hemp-production/Fertility.

Valtcho D Jeliazkov, Jay Noller, Sam Angima, Silvia I Rondon, Richard J Roseberg, Sunny Summers, Gordon Jones, Vladimir Sikora. 2019. What is Industrial Hemp?. Oregon State University Extension Service. https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9240.pdf

AGR - Suitability for Savanna Restoration

A savanna has been defined as a plant community where woody and herbaceous species co-dominate and the woody canopy is discontinuous such that the herbaceous species have adequate light to survive. The savanna land cover is, and historically has been, found in many different regions of the United States and indeed around the world. Despite differences in soils and climate geographically, savannas everywhere have some traits in common. First, they typically occur in somewhat water-limited environments. Where effective rainfall, that is rainfall in excess of evapotranspiration, is relatively abundant, savannas occurs where soil water storage is low. For example, this would typically describe the setting for the southeastern longleaf pine savannas. Where effective precipitation is limited, savannas occur where the soil water storage is relatively high. For example, bur oak savannas are found across the Midwest and Great Plains and in some western rangelands. Second, savannas are typically found on deep, well-drained soils. It is thought that these soils favor deep-rooted trees and perennial grasses. Savannas are generally not found on soils and landscapes subject to frequent flooding, frequent ponding, and high water tables. Third, the vegetation and landscape are conducive to frequent burning as is indicated by a historical fire return interval of 3 to 10 years. The fire return frequency is critical and lack of burning is a major factor in the afforestation of savannas. Longleaf pine, shortleaf pine, and bur oak, among others, are fire-resistant species that are found in areas of frequent burning, which can perpetuate or promote savanna conditions.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are thought to be able to sustain a savanna ecosystem. Numerical ratings indicate the degree of suitability associated with each soil or site feature. The ratings are shown in decimal fractions ranging from 0.0 to 1.00. They indicate gradations between the point at which a soil feature imparts the greatest degree of suitability (1.00) and the point at which the soil feature is the least suitable for savanna restoration (0.00).

Verbal ratings are defined as follows:

Well suited for savanna restoration (rating index 0.9 to 1.0)., The soil and site properties present are such that the conditions are very similar to known savannas. The climate, soil, and fire regime are well suited for savanna and maintenance will require few, if any, additional inputs.

Suited for savanna restoration (rating index is greater than 0.75 but less than 0.9)., The soil and site properties present are such that the conditions are similar to known savannas. The climate, soil, and fire regime are suited for savanna but some maintenance of the biome may require some additional inputs.

Somewhat suited for savanna restoration (rating index is greater than 0.2 but less than 0.75)., The soil and site properties present are such that the conditions are generally similar to known savannas, but with some deviation in fire regime, water storage, or effective precipitation. The climate, soil, and fire regime are somewhat suited for savanna but maintenance of the biome will require some additional inputs.

Not suited for savanna restoration (rating index is less than 0.2)., The soil and site properties present are such that the conditions are generally unlike known savannas. The site may be excessively wet, too steep, or in a region of infrequent historical burning.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Resources

Abdi, A.M., M. Brandt, C. Abel, R. Fensholt. 2022. Satellite Remote Sensing of Savannas: Current Status and Emerging Opportunities. Journal of Remote Sensing Volume 2022, Article ID 9835284.

Berry R.S.,. Kulmatiski. 2017. A savanna response to precipitation intensity. PLoS ONE 12 (4): e0175402. https://doi.org/10.1371/journal.

Das, A., A. Hird, B. Maharjan, M. Stephenson, L. Kariyawasam. 2024. Reference site selection based on state-and-transition models for Soil Quality gap evaluation within cropland reference ecological units. Soil Security 16 (2024) 100142.

Denevan, W. M. 1992. The Pristine Myth: The Landscape of the Americas in 1492, Annals of the Association of American Geographers, 82:3, 369-385.

Fowler, N. L., B. Beckage. 2020. Savannas of North America. Chapter 5 IN Savanna Woody Plants and Large Herbivores, First Edition. Edited by Peter Frank Scogings and Mahesh Sankaran. John Wiley & Sons Ltd.

Frost, C.C., 1998. Presettlement fire frequency regimes of the United States: a first approximation. In: Pruden, T.L., Brennan, L.A. (Eds.), Fire in Ecosystem Management: Shifting the Paradigm from Exclusion to Prescription. Tall Timbers Fire Ecology Conference Proceedings 20, Tall Timbers Research Station, Tallahassee, Florida, USA, pp 70, 81.

Goslee, S., M. Sanderson, K. Spaeth, J. Herrick, K. Ogles. 2014. An ecologically based landscape classification system for monitoring and assessment of pastures. JOURNAL OF SOIL AND WATER CONSERVATION, JAN/FEB 2014, VOL. 69, NO. 1.

Hanberry, B.B., Nowacki, G.J., 2016. Oaks were the foundation genus of the east-central United States. Quat. Sci. Rev. 145, 94, 103.

Lehmann, C.E.R., S. A. Archibald, W. A. Hoffmann, W. J. Bond. 2011. Deciphering the distribution of the savanna biome. New Phytologist (2011) 191: 197, 209.

"Catastrophic Event, Large Animal Mortality, Burial", is a method of disposing of deceased animals as a result of a large scale natural disaster such as a hurricane. The animals are disposed of by placing the carcasses in successive layers in an excavated and sloped pit. The carcasses are spread, compacted, and covered daily with a thin layer of soil that is excavated from the pit. When the pit is full, a final cover of soil material at least 2 feet thick is placed over the burial pit.

Soils are rated based on their limitation for burial of large animals following a catastrophic event. Catastrophic events include, but are not limited to, hurricanes, wildfires, flooding, and tornados. Limitations for burial of large animals during a catastrophic event are based primarily on contamination of groundwater, trafficability of excavation equipment, site selection, and site reclamation.

While some general observations may be made, onsite evaluation is required before the final site is selected. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater. Potential contamination may be reduced or eliminated by installing systems designed to overcome or reduce the effects of the limiting soil property. The rating is for soils in their present condition and does not consider present land use.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 or 7 feet). However, because pits may be as deep as 15 feet or more, geologic investigations are needed to determine the potential for pollution of ground water as well as to determine the design needed. These investigations, which are generally arranged by the pit developer, include the examination of stratification, rock formations, and geologic conditions that might lead to the conducting of leachates to aquifers, wells, watercourses, and other water sources. The presence of hard, nonrippable bedrock, bedrock crevices, or highly permeable strata in or immediately underlying the proposed pit bottom is undesirable because of the difficulty in excavation and the potential contamination of underground water.

Properties that influence the risk of contamination of groundwater, ease of excavation, trafficability, and revegetation are major considerations. Soils that flood or have a water table within the depth of excavation present a potential contamination hazard and are difficult to excavate. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the pit. It may also cause difficulty in constructing pits for which the pit bottom must be kept level and oriented to follow the contour.

The ease with which the pit is dug and with which a soil can be used as daily and final covers is based largely on texture and consistence of the soil. The texture and consistence of a soil determine the degree of workability of the soil both when dry and when wet. Soils that are plastic and sticky when wet are difficult to excavate, grade, or compact and difficult to place as a uniformly thick cover over a layer of carcasses. The uppermost part of the final cover should be soil material that is favorable for the growth of plants. It should not contain excess sodium or salt and should not be too acid. In comparison with other horizons, the A horizon in most soils has the best workability and the highest content of organic matter. Thus, for a Large Animal Disposal, Burial operation it may be desirable to stockpile the surface layer for use in the final blanketing of the filled pit area. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses.

Not limited (rating index equals 0) - The limitation for large animal disposal during a catastrophic event is insignificant. This soil is able to support standard excavation equipment, the soil has minimal contamination of groundwater, and soil reclamation using conventional processes is possible. Not limited soils have features that are very favorable for the specified use. Very good performance and very low maintenance can be expected of a properly designed and installed system.

Slightly limited (rating index greater than 0 but less than 0.30) - The limitation for large animal disposal during a catastrophic event is slightly limited. There are one or more soil properties that pose a slight limitation for contamination of groundwater, site reclamation, or excavation equipment. Slightly limited indicates the soil have features that are favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Good performance and low maintenance can be expected.

Somewhat limited (greater than 0.30 but less than 0.80) - The limitation for large animal disposal during a catastrophic event is somewhat limited. There are more than one soil properties that pose a limitation for contamination of groundwater, site reclamation, or excavation equipment. Any corrective measures taken to overcome these limitations are considered economical however, special care must be taken to overcome limitations. Somewhat limited indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. Severely limited (greater than 0.80 but less than 0.99) - The limitation for large animal disposal during a catastrophic event is severely limited. There are many soil properties that pose a limitation for contamination of groundwater, site reclamation, or excavation equipment. Additionally, corrective measures will be needed to overcome these limitations. Corrective measures taken may be costly to overcome limitations that pose a severely limited rating. Severely limited indicates that the soil has features that are unfavorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation however, it is costly to do so. Poor performance and high maintenance can be expected.

Very severely limited (rating index equals 1.0) - The limitation for large animal disposal during a catastrophic event is severely limited. There are one or more soil properties that pose a very severe limitation for contamination of groundwater, site reclamation, or excavation equipment. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Very poor performance and very high maintenance can be expected.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

"Catastrophic Event, Large Animal Disposal, Incinerate", is a method of disposing dead animals by placing the carcasses in a shallow excavated pit 91 cm (about 36 inches) deep or less. The carcasses are spread, compacted, and burned using established industry incineration techniques. Once carcasses have been sufficiently incinerated, a final cover of soil material at least 2 feet thick is placed over the burial pit.

Soils are rated based on their limitation for burial of large animals following a catastrophic event. Catastrophic events include, but are not limited to, hurricanes, wildfires, flooding, and tornados. Limitations for burial of large animals during a catastrophic event are based primarily on contamination of groundwater, trafficability of excavation equipment, site selection, and site reclamation.

While some general observations may be made, onsite evaluation is required before the final site is selected. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater. Potential contamination may be reduced or eliminated by installing systems designed to overcome or reduce the effects of the limiting soil property. The rating is for soils in their present condition and does not consider present land use.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 or 7 feet). However, geologic investigations are needed to determine the potential for pollution of ground water as well as to determine the design needed. These investigations, which are generally arranged by the pit developer, include the examination of stratification, rock formations, and geologic conditions that might lead to the conducting of leachates to aquifers, wells, watercourses, and other water sources. The presence of hard, nonrippable bedrock, bedrock crevices, or highly permeable strata in or immediately underlying the proposed pit bottom is undesirable because of the difficulty in excavation and the potential contamination of underground water.

Properties that influence the risk of contamination of groundwater, ease of excavation, trafficability, and revegetation are major considerations. Soils that flood or have a water table within the depth of excavation present a potential contamination hazard and are difficult to excavate. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the pit. It may also cause difficulty in constructing pits for which the pit bottom must be kept level and oriented to follow the contour.

The ease with which the pit is dug and with which a soil can be used as daily and final covers is based largely on texture and consistence of the soil. The texture and consistence of a soil determine the degree of workability of the soil both when dry and when wet. Soils that are plastic and sticky when wet are difficult to excavate, grade, or compact and difficult to place as a uniformly thick cover over a layer of carcasses. The uppermost part of the final cover should be soil material that is favorable for the growth of plants. It should not contain excess sodium or salt and should not be too acid. In comparison with other horizons, the A horizon in most soils has the best workability and the highest content of organic matter. Thus, for a Large Animal Disposal, Burial operation it may be desirable to stockpile the surface layer for use in the final blanketing of the filled pit area. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

Definitions of the ratings: Not limited (rating index = 0) - The limitation for large animal incineration during a catastrophic event is insignificant. This soil is able to support standard excavation equipment, the soil has minimal contamination of groundwater, and soil reclamation using conventional processes is possible. Not limited soils have features that are very favorable for the specified use. Very good performance and very low maintenance can be expected of a properly designed and installed system.

Slightly limited (rating index greater than 0 and less than 0.30) - The limitation for large animal incineration during a catastrophic event is slightly limited. There are one or more soil properties that pose a slight limitation for contamination of groundwater, site reclamation, or excavation equipment. Slightly limited indicates the soil has features that are favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Good performance and low maintenance can be expected.

Somewhat limited (greater than 0.30 and less than 0.80) - The limitation for large animal incineration during a catastrophic event is somewhat limited. There are more than one soil properties that pose a limitation for contamination of groundwater, site reclamation, or excavation equipment. Any corrective measures taken to overcome these limitations are considered economical however, special care must be taken to overcome limitations. Somewhat limited indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected.

Severely limited (greater than 0.80 and less than 0.99) - The limitation for large animal incineration during a catastrophic event is severely limited. There are many soil properties that pose a limitation for contamination of groundwater, site reclamation, or excavation equipment. Additionally, corrective measures will be needed to overcome these limitations. Corrective measures taken may be costly to overcome limitations that pose a severely limited rating. Severely limited indicates that the soil has features that are unfavorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation however, it is costly to do so. Poor performance and high maintenance can be expected.

Very severely limited (rating index equals 1.0) - The limitation for large animal incineration during a catastrophic event is severely limited. There are one or more soil properties that pose a very severe limitation for contamination of groundwater, site reclamation, or excavation equipment. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Very poor performance and very high maintenance can be expected. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

"Catastrophic mortality, large animal disposal, pit," is a method of disposing of animals that died from disease by placing the carcasses in successive layers in an excavated trench. The carcasses are spread, compacted, and covered daily with a thin layer of soil that is excavated from the pit. When the pit is full, a final cover of soil material at least 2 feet thick is placed over the filled pit area. This interpretation is meant for instances where environmental isolation of pathogens is a primary concern. The criteria are specifically developed to prevent groundwater contamination.

The interpretation is applicable to both heavily populated and sparsely populated areas. While some general observations may be made, onsite evaluation is required before the final site is selected. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater. The risk of contamination can be reduced or eliminated by installing systems designed to eliminate or reduce the adverse effects of limiting soil properties. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 or 7 feet). However, because pits may be as deep as 15 feet or more, geologic investigations are needed to determine the potential for pollution of ground water and to determine the design needed. These investigations, which are generally arranged by the pit developer, include examination of stratification, rock formations, and geologic conditions that might lead to the conducting of leachates to aquifers, wells, watercourses, and other water sources. The presence of hard, nonrippable bedrock, bedrock crevices, or highly permeable strata at or directly below the proposed pit bottom is undesirable because of the difficulty in excavation and the potential pollution of underground water.

Properties that influence the risk of pollution, ease of excavation, trafficability, and revegetation are major considerations. Soils that are flooded or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the pit. It may also cause difficulty in constructing pits in which the pit bottom must be kept level and oriented to follow the contour of the land.

The ease with which the pit is dug and with which a soil can be used as daily and final cover is based largely on soil texture and consistence, which determine workability when the soil is dry and when it is wet. Soils that are plastic and sticky when wet are difficult to excavate, grade, or compact and difficult to place as a uniformly thick cover over a layer of carcasses. The uppermost part of the final cover should be soil material that favors the growth of plants. It should not contain excess sodium or salts and should not be too acid. In comparison with other horizons, the surface layer in most soils has the best workability and the highest content of organic matter. Thus, it may be desirable to stockpile the surface layer for use in the final blanketing of the filled pit area.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected of a properly designed and installed system. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

"Catastrophic mortality, large animal disposal, trench," is a method of disposing of animals that died from disease by placing the carcasses in successive layers in an excavated trench. The carcasses are spread, compacted, and covered daily with a thin layer of soil that is excavated from the trench. When the trench is full, a final cover of soil material at least 2 feet thick is placed over the filled trench area. This interpretation is meant for instances where environmental isolation of pathogens is a primary concern. The criteria are specifically developed to prevent groundwater contamination.

The interpretation is applicable to both heavily populated and sparsely populated areas. While some general observations may be made, onsite evaluation is required before the final site is selected. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater. The risk of contamination can be reduced or eliminated by installing systems designed to eliminate or reduce the adverse effects of limiting soil properties. Ratings are for soils in their present condition. The present land use is not considered in the ratings.

Ratings are based on properties and qualities to the depth normally observed during soil mapping (approximately 6 or 7 feet). Because trenches may be as deep as 15 feet or more, however, geologic investigations are needed to determine the potential for pollution of ground water and to determine the design needed. These investigations, which are generally arranged by the trench developer, include examination of stratification, rock formations, and geologic conditions that might lead to the conducting of leachates to aquifers, wells, watercourses, and other water sources. The presence of hard, nonrippable bedrock, bedrock crevices, or highly permeable strata at or directly below the proposed trench bottom is undesirable because of the difficulty in excavation and the potential pollution of underground water.

Properties that influence the risk of pollution, ease of excavation, trafficability, and revegetation are major considerations. Soils that are flooded or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the trench. It may also cause difficulty in constructing trenches in which the trench bottom must be kept level and oriented to follow the contour of the land.

The ease with which the trench is dug and with which a soil can be used as daily and final cover is based largely on soil texture and consistence, which determine workability when the soil is dry and when it is wet. Soils that are plastic and sticky when wet are difficult to excavate, grade, or compact and difficult to place as a uniformly thick cover over a layer of carcasses. The uppermost part of the final cover should be soil material that favors the growth of plants. It should not contain excess sodium or salts and should not be too acid. In comparison with other horizons, the surface layer in most soils has the best workability and the highest content of organic matter. Thus, it may be desirable to stockpile the surface layer for use in the final blanketing of the fill.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected of a properly designed and installed system. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Using natural clayey soil material to line the bottom of a landfill pit is a method of assist in the sealing the pit that may have excessively high water transmission capabilities in the soil layer below the excavation. This interpretation shows the degree and kinds of properties that make soil material suitable for use as a clay liner.

The soil is evaluated from the surface to 79 inches. The ratings are based on the soil properties that affect ease of excavation, compactability of the material, the thickness of the soil layer, reclamation of the area, and erosion from the site.

Soils that flood or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Soils that are shallow to bedrock, ice, a cemented pan, or stones and boulders are limited because these features interfere with the excavation of the site or the suitability of the material. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the borrow area.

The ratings are both verbal and numerical. Numerical ratings in the table indicate the level of suitability of the soil as a clay liner source. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for this use. "Good" indicates that the soil has characteristics that are favorable for the specified use. The liner will have good performance and the material will not need any amendments to enhance its performance. "Fair" indicates that the soil has features that are moderately favorable for the specified use. The suitability as a liner may be enhanced by making a thicker layer, or adding bentonite to the soil material used for the liner. The soil may be difficult to work or contain rock fragments. "Poor" indicates that the soil has one or more features that are unfavorable for the specified use. While any material could be used as a clay liner, a poorly suited material will require large amounts of bentonite or other sealing material in order to achieve the expected level of performance.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

. Natural Resources Conservation Service. 1997. Agricultural Waste management Field Handbook. Chapter 10. 31 pages.

US Army Corps of Engineers. August 2004. Unified Facilities Guide Specifications No. 023377. 17 pages. http://www.ccb.org/docs/ufgshome/pdf/02377.pdf

Composting is a method of using natural processes to change vegetative debris into a useful product. This interpretation shows the degree and kind of limitations that affect the siting of a subsurface composting facility to stabilize vegetative debris produced as a result of a major disaster.

The soil is evaluated from the surface to a depth of 79 inches. The ratings are based on the soil properties that affect attenuation of suspended, soil solution, and gaseous decomposition products and microorganisms, construction and maintenance of the site, and public health. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater.

Properties that influence the risk of pollution, ease of excavation, trafficability, and revegetation are major considerations. Soils that flood or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Soils that have high saturated hydraulic conductivity (Ksat) are shallow to bedrock, ice, or a cemented pan, or have a high content of stones and boulders are limited because these features interfere with the installation, performance, and maintenance of the system. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the excavation. It may also cause difficulty in constructing trenches which must be kept level and oriented to follow the ground contour.

Climatic factors influence the ease with which a composting facility can be maintained. Adequate precipitation to keep the mass moist, and sufficient heat to sustain biological activity are essential.

The ratings are both verbal and numerical. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected of a properly designed and installed system on these soils. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Composting is a method of using natural processes to change vegetative debris into a useful product. This interpretation evaluates the degree and kind of limitation(s) that affect the siting of a surface composting facility to stabilize vegetative debris produced as a result of a major disaster.

The soil is evaluated from the surface to a depth of 79 inches. The ratings are based on the soil properties that affect trafficability; attenuation of suspended, soil solution, and gaseous decomposition products and microorganisms; construction and maintenance of the site; and public health. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater.

Properties that influence the risk of pollution, ease of excavation, trafficability, and revegetation are major considerations. Soils that flood or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Soils that have high saturated hydraulic conductivity (Ksat), that are shallow to bedrock, ice, or a cemented pan, or that have a high content of stones and boulders are limited because these features interfere with the installation, performance, and maintenance of the system. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the facility.

Climatic factors influence the ease with which a composting facility can be maintained. Adequate precipitation to keep the mass moist, and sufficient heat to sustain biological activity are essential.

The ratings are both verbal and numerical. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest limitation on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected of a properly designed and installed system on these soils. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Using natural soil material to assist in the biological degradation of organic material and as a capping for the mass of compost is common practice. This interpretation shows the degree and kinds of properties that make soil material suitable for use as composting medium and final cover material. Each soil is rated as a potential source of such material.

The soil is evaluated from the surface to 79 inches. The ratings are based on the soil properties that affect ease of excavation, workability of the material, the thickness of the soil layer, reclamation of the area, and erosion from the site.

Soils that flood or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Soils that are shallow to bedrock, ice, a cemented pan, or stones and boulders are limited because these features interfere with the excavation of the site or the suitability of the material. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the borrow area.

The ratings are both verbal and numerical. Numerical ratings in indicate the level of suitability of the soil as a composting medium and final cover material source. The ratings are shown in decimal fractions ranging from 1.00 to 0.01. They indicate gradations between the point at which a soil feature has the greatest positive impact on the use (1.00) and the point at which the soil feature has the greatest negative impact (0.00).

Rating class terms indicate the extent to which the soils are made suitable by all of the soil features that affect the suitability of soil material for this use. "Good" indicates that the soil has characteristics that are favorable for the specified use. The compost medium or final cover material will have good performance. "Fair" indicates that the soil has features that are moderately favorable for the specified use. The soil may be somewhat difficult to work or contain rock fragments. "Poor" indicates that the soil has one or more features that are unfavorable for the specified use. While any material could be used as a composting medium and final cover material, a poorly suited material will require large amounts of amendments or screening in order to achieve the expected level of performance.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

"Emergency Animal Mortality Disposal by Shallow Burial" is a method of disposing of depopulated animals as a result of a large-scale natural disaster. Catastrophic events include, but are not limited to, hurricanes, wildfires, flooding, supply chain disruptions, and tornados. This disposal method employs a shallow trench, about 2 feet deep and wide enough to accommodate the mortalities. The trench is first lined with 6 to 12 inches of carbonaceous material, such as corn stalks or wood chips. The animals are then placed in a single layer in the excavation. When the trench is full, a final cover of soil material at least 2 feet thick, extending above grade, is placed over the burial pit and vegetation is established. Soils are rated based on their limitation for burial of large animals following a catastrophic event. Limitations for burial of large animals after or during a catastrophic event are based primarily on contamination of ground water, trafficability of excavation equipment, site selection, and site reclamation.

While some general observations may be made, onsite evaluation is required before the final site is selected. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater. Potential contamination may be reduced or eliminated by installing systems designed to overcome or reduce the effects of the limiting soil property. The rating is for soils in their present condition and does not consider present land use.

Since this is a new interpretation, users are encouraged to give feedback as to the usefulness of the interpretation or the appropriateness of the criteria. Comments may be sent through the Soils Hotline (SoilsHotline@lin.usda.gov).

Ratings are based on the soil properties and qualities normally observed (to a depth of approximately 6 or 7 feet) during soil mapping. These investigations, which are generally arranged by the pit developer, include the examination of stratification, rock formations, and geologic conditions that may allow leachates to enter aquifers, wells, watercourses, and other water sources. Hard, nonrippable bedrock, bedrock crevices, or highly permeable strata in or immediately underlying the proposed pit bottom are undesirable because of the difficulty in excavation and the potential contamination of ground water.

Properties that influence the risk of contamination of ground water, ease of excavation, trafficability, and revegetation are major considerations. Soils that flood or have a water table within the depth of excavation present a potential contamination hazard and are difficult to excavate. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the site. It may also make pit construction difficult because the pit bottom must be kept level and oriented to follow the contour.

The ease with which the pit is dug and with which a soil can be used as daily and final covers is based largely on texture and consistence of the soil. Soil texture and consistence determine the degree of workability of the soil both when dry and when wet. Soils that are plastic and sticky when wet are difficult to excavate, grade, or compact and difficult to place as a uniformly thick cover over a layer of carcasses. The uppermost part of the final cover should be soil material that is favorable for the growth of plants. It should not contain excess sodium or salt and should not be too acid. In comparison with other horizons, the A horizon in most soils has the best workability and the highest content of organic matter. Thus, for a "Large Animal Disposal, Burial" operation it may be desirable to stockpile the surface layer for use in the final blanketing of the filled pit area.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

Verbal ratings are defined as follows:

Not limited (rating index equals 0)., The limitation for large animal disposal during a catastrophic event is insignificant. The soil is able to support standard excavation equipment, the risk of ground-water contamination is minimal, and soil reclamation using conventional processes is possible. The soil has features that are very favorable for the specified use. Very good performance and very low maintenance can be expected if the system is properly designed and installed.

Slightly limited (rating index is greater than 0 but less than 0.30)., The limitation for large animal disposal during a catastrophic event is slightly limited. There are one or more soil properties that pose a slight limitation for contamination of ground water, site reclamation, or excavation equipment. The soil has features that are favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Good performance and low maintenance can be expected.

Somewhat limited (rating index is greater than 0.30 but less than 0.80)., The limitation for large animal disposal during a catastrophic event is somewhat limited. The soil has features that are moderately favorable for the specified use; there are more than one soil properties that pose a limitation for contamination of ground water, site reclamation, or excavation equipment. Corrective measures needed to overcome these limitations are considered economical; however, special care must be taken. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected.

Severely limited (rating index is greater than 0.80 but less than 0.99)., The limitation for large animal disposal during a catastrophic event is severely limited. The soil has features that are unfavorable for the specified use; there are many soil properties that pose a limitation for contamination of ground water, site reclamation, or excavation equipment. The limitations can be overcome or minimized by special planning, design, or installation; however, correction measures are costly. Poor performance and high maintenance can be expected.

Very severely limited (rating index equals 1.0)., The limitation for large animal disposal during a catastrophic event is severely limited. There are one or more soil properties that pose a very severe limitation for contamination of ground water, site reclamation, or excavation equipment. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Very poor performance and very high maintenance can be expected.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Reference:

Flory, G.A., R.W. Peer, R.A Clark, M.N. Baccar, T.T. Le, A.B. Mbarek, and S. Farsi. 2017. Aboveground burial for managing catastrophic losses of livestock. International Journal of One Health 3:50-56.

Emergency Land Application of Milk

Disruptions in the supply chain and other problems can necessitate the emergency land disposal of milk. Land application is a viable method of disposal as the constituents of milk can be beneficial as soil amendments. The characteristics of the soil are important in the application since favorable soil properties are required to prevent environmental damage.

Soils can be a non-member, partial member, or complete members of the set of soils that are limited for "Emergency Land Application of Milk". If a soil property within 150 cm (60 inches) of the soil surface has a membership index greater than zero, then that soil property is limiting, and the soil restrictive feature is identified. The overall interpretive rating assigned is the maximum membership indices of each soil interpretive property that comprise the "Emergency Land Application of Milk" interpretive rule. Minor restrictive soil features are identified but not considered as part of the overall rating process. These restrictive features could be important factors where the major restrictive features are overcome through design application.

Soil properties and qualities considered are those that affect liquid movement into and through the soil, the ability of the soil to attenuate material, the slope of the land surface, the presence of rock fragments, and the volume of soil available for absorbing the milk solids. Soil properties that affect absorption are permeability, the depth to a seasonal high water table, and the depth to bedrock or a cemented pan. Stones and the depth to a seasonal high water table can interfere with the application of milk. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

Definitions of the ratings:

Not limited (rating index equals 0) - The limitation for land disposal of milk during a catastrophic event is insignificant. This soil is able to support standard application equipment, the soil has minimal risk of allowing groundwater contamination, and surface water contamination risk is low.

Slightly limited (rating index greater than 0 but less than 0.33) - The limitation for land disposal of milk during a catastrophic event is slightly limited. There are one or more soil properties that pose a slight limitation for contamination of groundwater, surface runoff, or application equipment.

Somewhat limited (greater than 0.33 but less than 0.67) - The limitation for land disposal of milk during a catastrophic event is somewhat limited. There are more than one soil properties that pose a limitation for contamination of groundwater, surface runoff, or application equipment. Any corrective measures taken to overcome these limitations are considered economical however, special care must be taken to overcome limitations. Somewhat limited indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation.

Moderately limited (greater than 0.80 but less than 0.99) - The limitation for land disposal of milk during a catastrophic event is moderately limited. There are some soil properties that pose a limitation for contamination of groundwater, surface runoff, or application equipment limitations. Additionally, corrective measures will be needed to overcome these limitations. Corrective measures taken may be costly to overcome limitations that pose a severely limited rating. Moderately limited indicates that the soil has features that are unfavorable for the specified use.

Very limited (rating index equals 1.0) - The limitation for land disposal of milk during a catastrophic event is severe. There are one or more soil properties that pose a very severe limitation for contamination of groundwater, surface runoff, or application equipment limitations. The limitations generally cannot be overcome.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all the soil features that affect these uses.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Burial of rubble and debris in an expeditiously constructed landfill is a method of disposing of material that has been rendered unsafe and unusable by the effects of a large-scale disaster, either natural or man-made, often affecting tens of counties or parishes. Many homes and business structures are rendered unfit for occupancy, either by destruction or contamination. Such a landfill involves excavating a large pit or trench, placing the rubble and debris in the trench, and covering each layer with a blanket of soil material. A final blanket of cover material is placed over the whole facility when completed.

This interpretation shows the degree and kind of limitations that affect a soil's use for such a landfill. The soil is evaluated from the surface to 79 inches. An on-site investigation to greater depth will be needed for final site acceptance. The ratings are based on the soil properties that affect attenuation of suspended, soil solution, and gaseous decomposition products and microorganisms; construction and maintenance of the site; and public health. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater.

Properties that influence the risk of pollution, ease of excavation, trafficability, and revegetation are major considerations. Soils that flood or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Soils that have high saturated hydraulic conductivity (Ksat) or are shallow to bedrock, ice, a cemented pan, or stones and boulders are limited because these features interfere with the installation, performance, and maintenance of the system. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the excavation. It may also cause difficulty in constructing trenches for which the trench or pit bottom must be kept level and oriented to follow the ground contour.

The ease with which the trench or pit is dug and with which a soil can be used as daily and final covers is based largely on texture and consistence of the soil which affect the workability of the soil both when dry and when wet. Soils that are plastic and sticky when wet are difficult to excavate, grade, or compact and difficult to place as a uniformly thick cover over a layer of rubble or debris. The uppermost part of the final cover should be soil material that is favorable for the growth of plants. It should not contain excess sodium or salt and should not be too acid. In comparison with other horizons, the A horizon in most soils has the best workability and the highest content of organic matter. Thus, for a rubble and debris disposal operation it may be desirable to stockpile the surface layer for use in the final blanketing of the filled area.

The ratings are both verbal and numerical. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected of a properly designed and installed system on these soils. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Severely limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Introduction The U.S. Federal Geographic Data Committee (FGDC) established a standard for estuarine, coastal, or open-ocean settings to provide a way to organize and interpret data about the marine environment called The Coastal and Marine Ecological Classification Standard (CMECS). CMECS strives to be compatible with ongoing and future activities such as coastal zone soil survey mapping; although, it is not based on quantitative analysis of new data. To identify and map lower-level features like the substrate subgroup, data collection is necessary.

This interpretation gives the CMECS substrate component classification for the soils in subaqueous areas. The report is calculated based on the soil surface horizon to provide the CMECS terminology for substrate origin, substrate class, substrate subclass, substrate group, and substrate subgroup.

Substrate Component Substrate is defined in CMECS as the non-living materials that form an aquatic bottom or seafloor, or that provide a surface (e.g., floating objects, buoys) for growth of attached biota. Substrate may be composed of any substance, natural or synthetic. The substrate component (SC) is a characterization of the composition and particle size of the surface layers of the substrate. The surface layers may be the upper layer of hard substrate, or (typically) the upper 15 centimeters of soft substrate.

Substrate component classification structure:

Substrate Origin, The first level of classification in the SC is substrate origin, which is subdivided into geologic substrate, biogenic substrate, and anthropogenic substrate. The substrate origin type is assigned based on dominance (greatest percent cover) of either the geologic, biogenic (but no longer living), or anthropogenic upper layer of substrate.

Substrate Classes and Subclasses, Substrate classes and substrate subclasses are determined by the composition and particle size of the dominant substrate origin in the surface sediments.

Substrate Groups and Subgroups, Substrate groups and substrate subgroups are determined by Folk's (1954) mixes for geologic sediments and by taxa for the biogenic substrates. Groups and subgroups are not used for anthropogenic substrates.

For this interpretation, soils that have surface layers with an organic matter greater than 8.6 percent or have a peat texture are labeled as organic substrate. If the texture class is peat, then it is labeled peat debris; and if it has greater than 8.6 percent organic matter, then it is labeled organic mud.

References Folk, Robert. 1954. Folk's Classification of Sediments.

U.S. Federal Geographic Data Committee. 2012. Coastal and Marine Ecological Classification Standard. FGDC-STD-18-2012.

Introduction The U.S. Federal Geographic Data Committee (FGDC) established a standard for estuarine, coastal, or open-ocean settings to provide a way to organize and interpret data about the marine environment called The Coastal and Marine Ecological Classification Standard (CMECS). CMECS strives to be compatible with ongoing and future activities such as coastal zone soil survey mapping; although, it is not based on quantitative analysis of new data. To identify and map lower-level features like the substrate subgroup, data collection is necessary.

This interpretation gives the CMECS substrate component classification for the soils in subaqueous areas. The report is calculated based on the soil surface horizon to provide the CMECS terminology for substrate origin, substrate class, substrate subclass, substrate group, and substrate subgroup.

Substrate Component Substrate is defined in CMECS as the non-living materials that form an aquatic bottom or seafloor, or that provide a surface (e.g., floating objects, buoys) for growth of attached biota. Substrate may be composed of any substance, natural or synthetic. The substrate component (SC) is a characterization of the composition and particle size of the surface layers of the substrate. The surface layers may be the upper layer of hard substrate, or (typically) the upper 15 centimeters of soft substrate.

Substrate component classification structure:

Substrate Origin, The first level of classification in the SC is substrate origin, which is subdivided into geologic substrate, biogenic substrate, and anthropogenic substrate. The substrate origin type is assigned based on dominance (greatest percent cover) of either the geologic, biogenic (but no longer living), or anthropogenic upper layer of substrate.

Substrate Classes and Subclasses, Substrate classes and substrate subclasses are determined by the composition and particle size of the dominant substrate origin in the surface sediments.

Substrate Groups and Subgroups, Substrate groups and substrate subgroups are determined by Folk's (1954) mixes for geologic sediments and by taxa for the biogenic substrates. Groups and subgroups are not used for anthropogenic substrates.

For this interpretation, soils that have surface layers with an organic matter greater than 8.6 percent or have a peat texture are labeled as organic substrate. If the texture class is peat, then it is labeled peat debris; and if it has greater than 8.6 percent organic matter, then it is labeled organic mud.

References Folk, Robert. 1954. Folk's Classification of Sediments.

U.S. Federal Geographic Data Committee. 2012. Coastal and Marine Ecological Classification Standard. FGDC-STD-18-2012.

Introduction The U.S. Federal Geographic Data Committee (FGDC) established a standard for estuarine, coastal, or open-ocean settings to provide a way to organize and interpret data about the marine environment called The Coastal and Marine Ecological Classification Standard (CMECS). CMECS strives to be compatible with ongoing and future activities such as coastal zone soil survey mapping; although, it is not based on quantitative analysis of new data. To identify and map lower-level features like the substrate subgroup, data collection is necessary.

This interpretation gives the CMECS substrate component classification for the soils in subaqueous areas. The report is calculated based on the soil surface horizon to provide the CMECS terminology for substrate origin, substrate class, substrate subclass, substrate group, and substrate subgroup.

Substrate Component Substrate is defined in CMECS as the non-living materials that form an aquatic bottom or seafloor, or that provide a surface (e.g., floating objects, buoys) for growth of attached biota. Substrate may be composed of any substance, natural or synthetic. The substrate component (SC) is a characterization of the composition and particle size of the surface layers of the substrate. The surface layers may be the upper layer of hard substrate, or (typically) the upper 15 centimeters of soft substrate.

Substrate component classification structure:

Substrate Origin, The first level of classification in the SC is substrate origin, which is subdivided into geologic substrate, biogenic substrate, and anthropogenic substrate. The substrate origin type is assigned based on dominance (greatest percent cover) of either the geologic, biogenic (but no longer living), or anthropogenic upper layer of substrate.

Substrate Classes and Subclasses, Substrate classes and substrate subclasses are determined by the composition and particle size of the dominant substrate origin in the surface sediments.

Substrate Groups and Subgroups, Substrate groups and substrate subgroups are determined by Folk's (1954) mixes for geologic sediments and by taxa for the biogenic substrates. Groups and subgroups are not used for anthropogenic substrates.

For this interpretation, soils that have surface layers with an organic matter greater than 8.6 percent or have a peat texture are labeled as organic substrate. If the texture class is peat, then it is labeled peat debris; and if it has greater than 8.6 percent organic matter, then it is labeled organic mud.

References Folk, Robert. 1954. Folk's Classification of Sediments.

U.S. Federal Geographic Data Committee. 2012. Coastal and Marine Ecological Classification Standard. FGDC-STD-18-2012.

Introduction The U.S. Federal Geographic Data Committee (FGDC) established a standard for estuarine, coastal, or open-ocean settings to provide a way to organize and interpret data about the marine environment called The Coastal and Marine Ecological Classification Standard (CMECS). CMECS strives to be compatible with ongoing and future activities such as coastal zone soil survey mapping; although, it is not based on quantitative analysis of new data. To identify and map lower-level features like the substrate subgroup, data collection is necessary.

This interpretation gives the CMECS substrate component classification for the soils in subaqueous areas. The report is calculated based on the soil surface horizon to provide the CMECS terminology for substrate origin, substrate class, substrate subclass, substrate group, and substrate subgroup.

Substrate Component Substrate is defined in CMECS as the non-living materials that form an aquatic bottom or seafloor, or that provide a surface (e.g., floating objects, buoys) for growth of attached biota. Substrate may be composed of any substance, natural or synthetic. The substrate component (SC) is a characterization of the composition and particle size of the surface layers of the substrate. The surface layers may be the upper layer of hard substrate, or (typically) the upper 15 centimeters of soft substrate.

Substrate component classification structure:

Substrate Origin, The first level of classification in the SC is substrate origin, which is subdivided into geologic substrate, biogenic substrate, and anthropogenic substrate. The substrate origin type is assigned based on dominance (greatest percent cover) of either the geologic, biogenic (but no longer living), or anthropogenic upper layer of substrate.

Substrate Classes and Subclasses, Substrate classes and substrate subclasses are determined by the composition and particle size of the dominant substrate origin in the surface sediments.

Substrate Groups and Subgroups, Substrate groups and substrate subgroups are determined by Folk's (1954) mixes for geologic sediments and by taxa for the biogenic substrates. Groups and subgroups are not used for anthropogenic substrates.

For this interpretation, soils that have surface layers with an organic matter greater than 8.6 percent or have a peat texture are labeled as organic substrate. If the texture class is peat, then it is labeled peat debris; and if it has greater than 8.6 percent organic matter, then it is labeled organic mud.

References Folk, Robert. 1954. Folk's Classification of Sediments.

U.S. Federal Geographic Data Committee. 2012. Coastal and Marine Ecological Classification Standard. FGDC-STD-18-2012.

Introduction The U.S. Federal Geographic Data Committee (FGDC) established a standard for estuarine, coastal, or open-ocean settings to provide a way to organize and interpret data about the marine environment called The Coastal and Marine Ecological Classification Standard (CMECS). CMECS strives to be compatible with ongoing and future activities such as coastal zone soil survey mapping; although, it is not based on quantitative analysis of new data. To identify and map lower-level features like the substrate subgroup, data collection is necessary.

This interpretation gives the CMECS substrate component classification for the soils in subaqueous areas. The report is calculated based on the soil surface horizon to provide the CMECS terminology for substrate origin, substrate class, substrate subclass, substrate group, and substrate subgroup.

Substrate Component Substrate is defined in CMECS as the non-living materials that form an aquatic bottom or seafloor, or that provide a surface (e.g., floating objects, buoys) for growth of attached biota. Substrate may be composed of any substance, natural or synthetic. The substrate component (SC) is a characterization of the composition and particle size of the surface layers of the substrate. The surface layers may be the upper layer of hard substrate, or (typically) the upper 15 centimeters of soft substrate.

Substrate component classification structure:

Substrate Origin, The first level of classification in the SC is substrate origin, which is subdivided into geologic substrate, biogenic substrate, and anthropogenic substrate. The substrate origin type is assigned based on dominance (greatest percent cover) of either the geologic, biogenic (but no longer living), or anthropogenic upper layer of substrate.

Substrate Classes and Subclasses, Substrate classes and substrate subclasses are determined by the composition and particle size of the dominant substrate origin in the surface sediments.

Substrate Groups and Subgroups, Substrate groups and substrate subgroups are determined by Folk's (1954) mixes for geologic sediments and by taxa for the biogenic substrates. Groups and subgroups are not used for anthropogenic substrates.

For this interpretation, soils that have surface layers with an organic matter greater than 8.6 percent or have a peat texture are labeled as organic substrate. If the texture class is peat, then it is labeled peat debris; and if it has greater than 8.6 percent organic matter, then it is labeled organic mud.

References Folk, Robert. 1954. Folk's Classification of Sediments.

U.S. Federal Geographic Data Committee. 2012. Coastal and Marine Ecological Classification Standard. FGDC-STD-18-2012.

Eastern Oyster (Crassostrea virginica) Habitat Restoration Suitability, A Subaqueous Soil Interpretation

Introduction

The Eastern oyster (Crassostrea virginica) is native to the eastern seaboard from the Gulf of St. Lawrence in Canada, south to the Gulf of Mexico coast of North America. Often concentrated on oyster bars, beds, or rocks, which are located in waterways with firm bottom areas, oysters attach to one another forming dense reefs that provide habitat for many fish and invertebrates.

Like all oysters, the Eastern oyster is a filter feeder. They draw in water and filter out plankton and detritus to digest, then discharge unwanted food items and particulate matter, thus cleaning the water around them. One oyster can filter more than 50 gallons of water in 24 hours. Oyster beds have an estimated 50 times the surface area of an equally sized flat bottom and attract a high concentration of larger predators looking for food (Eastern Oyster, 2016). Oysters are considered a keystone species in most estuaries along the Atlantic and Gulf coasts. Grabowski and Peterson (2007) recognized seven ecosystem services provided by Crassostrea virginica habitats. They are: (1) oyster production; (2) water filtration and concentration of pseudofeces; (3) provision of habitat for epibenthic invertebrates; (4) nutrient sequestration; (5) augmented fish production; (6) stabilization of adjacent habitats and shoreline; and (7) diversification of the landscape and ecosystem. Purpose

Despite their significance, oyster reefs are one of the most threatened marine habitats on earth. In the last decade, many people have come to support oyster restoration efforts for the purposes of conservation and provision of ecosystem services. Construction of oyster reefs is supported as an avenue for protecting biodiversity, regulating nutrients in estuaries through water filtration, protecting shorelines from erosion, and providing habitat for many estuarine species.

This soil interpretation is intended to help identify sites with appropriate soil (substrate) types for targeted oyster habitat restoration.

Soil Rating Classes

High Suitability: Soils in this rating class have a high potential for successful oyster restoration because they have the best soil properties or characteristics for a successful establishment of an oyster reef.

Moderate Suitability: Soils in this rating class have a moderate potential for successful oyster restoration due to one or more limiting soil properties or characteristics such as soil texture or electrical conductivity.

Low Suitability: Soils in this rating class have a low potential for successful oyster restoration due to multiple limiting soil properties or characteristics.

Not Suitable: Soils in this rating class are not suitable for oyster restoration because they are freshwater subaqueous soils that lack the appropriate salinity levels necessary to establish and grow oysters.

Not Rated: These soils or miscellaneous areas are not subaqueous soils; therefore, they are not rated as this soil interpretation should only take into consideration subaqueous and submerged soils.

References

Eastern Oyster. http://www.ereferencedesk.com/resources/state-gemstone/louisiana-gemstone.html (accessed May 2016).

Grabowski, J.H., and C.H. Peterson. 2007. Restoring oyster reefs to recover ecosystem services. In: Cuddington, K., J.E. Byers, W.G. Wilson, and A. Hastings (editors). Ecosystem Engineers: concepts, theory and applications. Elsevier- Academic Press, Amsterdam. p. 281-298.

Eelgrass Restoration Suitability A Subaqueous Soil Interpretation

Introduction

Submerged aquatic vegetation (SAV) is a term used to describe rooted, vascular plants that grow completely underwater except for periods of brief exposure at low tides. The term SAV is generally used for marine, estuarine, and riverine angiosperms and macrophytes.

Eelgrass, a kind of seagrass, is the only true marine SAV found in Long Island Sound and is Rhode Island's primary seagrass. Eelgrass, Zostera marina, is a flowering marine plant that forms extensive meadows or patchy beds interspersed with bare areas, and the location of these beds can shift over time. Eelgrass beds are always completely submerged, and their roots, known as rhizomes, anchor the grass to the soil.

Eelgrass beds rank among the most productive of marine and estuarine plant habitats. Eelgrass habitat supports an abundant diversity of life, stabilizes seafloor sediments and adjacent shorelines, helps maintain water quality, and is a critical component of the marine food web. Eelgrass grows in areas of specific, though diverse, environmental conditions. Substrate requirements range from sand and gravel to mud.

In Long Island Sound, eelgrass is found at depths between 0.5 and 3.6 meters below mean low water (Koch and Beer, 1996). In Rhode Island, eelgrass grows in nearshore waters at depths ranging from 1 to 4.5 meters. The upper limit of growth is determined by physical factors such as wave action, ice scour, and desiccation (LISHRI, 2003).

Purpose

Eelgrass habitat is at risk. Over the last century, seagrass coverage worldwide has declined by about 30 percent (WWF, 2015). During the 1930s, much of the eelgrass succumbed to wasting disease, a widespread infection partly attributed to the slime mold Labryinthula zosterae. Within two years, 90 percent of all eelgrass populations in the North Atlantic (from Canada to North Carolina) disappeared (Kerr et al., 2012).

This soil interpretation is intended to help identify appropriate site selection for eelgrass restoration. While conservation and protection of existing eelgrass beds are the best strategies for addressing this problem, restoring areas that supported eelgrass habitat in the past is a valuable management measure. Because the habitats are underwater, the cost of collecting, preparing, and planting eelgrass can be significant. With the availability of more subaqueous soils data, preliminary GIS analysis for successful eelgrass restoration site selections will be significantly improved. Soil Rating Classes

High Suitability: Soils in this rating class have a high potential for successful eelgrass restoration because they have the best soil properties or characteristics for a successful establishment of eelgrass beds.

Moderate Suitability: Soils in this rating class have a moderate potential for successful eelgrass restoration due to one or more somewhat limiting soil properties or characteristics such as water depth, percent silt and clay, percent organic matter, presence of reduced monosulfides, oxidized pH, and electrical conductivity.

Low Suitability: Soils in this rating class have a low potential for successful eelgrass restoration due to multiple limiting soil properties or characteristics.

Not Suitable: Soils in this rating class are not suitable for eelgrass restoration because they are freshwater subaqueous soils that lack the appropriate salinity levels necessary for the establishment and growth of eelgrass.

Not Rated: These soils or miscellaneous areas are not subaqueous soils; therefore, they are not rated.

References

Kerr, M., W. Ferguson, and M. Cole Ekberg. 2012. Eelgrass Restoration in Narragansett Bay. Narragansett Bay Journal, fall 2012

Kock, E.W. and S. Beer. 1996. Tides, light and the distribution of Zostera marina in Long Island Sound, USA. Aquatic Botany 53:97-107.

Long Island Sound Habitat Restoration Initiative. 2003. Habitat Restoration Technical Manual, Section 3: Submerged Aquatic Vegetation.

WWF. 2015. Living Blue Planet Report. Species, habitats and human well-being. In: Tanzer, J., Phua, C., Lawrence, A., Gonzales, A., Roxburgh, T. and P. Gamblin, editors. WWF, Gland, Switzerland.

Land Utilization of Dredged Materials A Subaqueous Soil Interpretation

Introduction Sulfidization, or the accumulation of sulfides, is an important soil forming process in estuarine and marine soils (Fanning and Fanning, 1989). In these settings, sulfate, the second most common anion in seawater, is reduced to sulfide through the metabolism of sulfate-reducing bacteria in the subsurface anaerobic soil (Jorgensen, 1977; Day et al., 1989).

Sulfide is most often trapped in the sediment by binding with metal ions such as iron (Fe) (Jorgensen, 1977). Sulfide content of soils is important when considering marine construction, dredging, and beach and dune nourishment projects. If sulfide bearing subaqueous soils are dredged and placed in a subaerial environment, sulfides will oxidize, creating sulfuric acid, drastically lowering soil pH (to a pH less than 4), and resulting in acid sulfate soils (Fanning and Fanning, 1989).

Acid sulfate soils may persist for a number of years and are uninhabitable for plants and animals. If deposited near water, these acid sulfate soils can also create runoff that is toxic to aquatic systems as metals such as aluminum, iron, manganese, copper, and lead become more soluble at a low pH (Demas et al., 2004). Anaerobic soils that contain high levels of sulfidic materials at a shallow depth (less than 200 cm) are referred to as potential acid sulfate soils (PASS). Their field pH is generally pH 4 or greater (SACPB, 2003).

Purpose The purpose of this soil interpretation is to identify subaqueous soils that have the potential to produce acid sulfate soils when dredged and placed on the land surface. This interpretation is rated as a limitation, with soils containing any sulfidic materials within 200 centimeters from the soil surface being ranked as limited for land utilization of dredged materials. Soil Rating Classes Soils are placed into interpretive rating classes per their rating indices. Either the presence of reduced monosulfides or an oxidized pH less than or equal to 4 in any soil layer within 200 centimeters from the soil surface will give the soil a rating of limited.

Limited: Soils in this rating class are considered potential acid sulfate soils and should not be dredged for upland utilization. The cost to the surrounding environment and inevitably to the upland development itself of releasing acid and metal ions into the soil and groundwater outweighs any short-term gain.

Not Limited: Soils in this rating class are not considered potential acid sulfate soils.

Not Rated: Soils or miscellaneous areas in this rating class are not subaqueous soils and should not be rated. A subaqueous drainage class is defined as having a positive water potential at the soil surface (i.e. inundation) for more than 21 hours of each day.

References Day, J.W. Jr., C.A.S. Hall, W.M. Kemp, and A. Yez-Arancibia. 1989. Estuarine Ecology. John Wiley & Sons, New York, NY. Demas, S.Y., A.M. Hall, D.S. Fanning, M.C. Rabenhorst, and E.K. Dzantor. 2004. Acid sulfate soils in dredged materials from tidal Pocomoke Sound in Somerset County, MD, USA. Australian Journal of Soil Research 42:537-545. Fanning, D.S. and M.C.B. Fanning. 1989. Soil morphology, genesis, and classification. John Wiley & Sons, New York, NY. Jorgensen, B.B. 1977. The sulfur cycle of a coastal marine sediment (Limfjorden, Denmark). Limnology and Oceanography 22:814-831. South Australian Coast Protection Board (SACPB). 2003. Coastline a strategy for implementing CPB policies on coastal acid sulfate soils in South Australia. No 33. p. 1-12.

Mooring Anchors: Deadweight, A Subaqueous Soil Interpretation

Introduction A mooring refers to a structure or anchor used to hold a boat in a certain area, with a float or buoy attached. Safety of a boat on a mooring depends on a number of elements, one of them is the type of bottom materials or soil. There are two primary classes of anchors, temporary and permanent. A permanent anchor, often called a mooring, is rarely moved. The anchor needs to hold the vessel in all weathers, including the most severe storms, and only needs to be lifted on rare occasions. Two common types of permanent anchors are the mushroom and deadweight anchors. The deadweight anchor is the focus of this soil interpretation.

Deadweight anchors work on the principle of being heavy. Whether the anchor is a block of stone, concrete, or iron, its holding power is weight. Deadweight anchors provide the greatest reliability. They are the best choice for rocky, gravelly, or sandy soils with low n-value soil surface layers or hard bottom types of material. If a deadweight anchor is dragged, it will resist with constant force. By contrast, once a mushroom anchor breaks free, it will not reset and will simply skip along the bottom. The disadvantage of using a deadweight anchor in conditions where a mushroom anchor could be used is that it needs to be around ten times the weight of the equivalent mushroom anchor (INAMAR, 2000).

Purpose Without the knowledge of what type of anchor is used and what type of soil material it is set in, the holding capacity of the mooring is compromised. The type of soil material has a great deal to do with the holding power of anchors. This soil interpretation is intended to help identify the type of soil material suitable for deadweight anchors. Soil Ratings

Soils are placed into interpretive rating classes per their rating indices. The rating indices finds the sum of the horizon thicknesses having each n-value condition between 0 and 150 centimeters. The n-value associated with the highest sum of horizon thicknesses is used to place the soil into a rating class.

Soils rated for deadwight moorings are either not limited, somewhat limited, very limited, or not rated.

Very Limited: Soils with a high n-value (very fluid) between 0 and 150 centimeters from the soil surface are rated very limited for deadweight anchors.

Somewhat Limited: Soils with an n-value of slightly or moderately fluid between 0 and 150 centimeters from the soil surface are rated somewhat limited for deadweight anchors.

Not Limited: Soils with a low n-value (nonfluid) between 0 and 150 centimeters from the soil surface are rated not limited for deadweight anchors.

Not Rated: Soils or miscellaneous areas that do not have a subaqueous drainage class are not rated.

Reference

INAMAR. 2000. Moorings: important recommendations for safe moorings from INAMAR. p. 1-8.

Mooring Anchors: Mushroom A Subaqueous Soil Interpretation

Introduction A mooring refers to a structure or anchor used to hold a boat in a certain area, with a float or buoy attached. Safety of a boat on a mooring depends on a number of elementsone of them is the type of bottom materials or soil. There are two primary classes of anchorstemporary and permanent. A permanent anchor, often called a mooring, is rarely moved. The anchor needs to hold the vessel in all weathers, including the most severe storms, and only needs to be lifted on rare occasions. Two common types of permanent anchors are the mushroom and deadweight anchors. The mushroom anchor is the focus of this soil interpretation.

A mushroom anchor is shaped like an inverted mushroom; the head becoming buried in the soil. These anchors work best in loamy to organic soils with high n-value surface layers or soft bottom types of material when they are left in and allowed to set. These anchors work on the principle of surface area and suction effect. Cohesion of the bottom material is very important. Rocks, gravel, or coarse sand lack good cohesive properties, allowing the anchor to pull free. Mushroom anchors in sand will not bury completely. They will only sink to displace an equal weight of sand. Their large, round dish design is not well suited to penetrating the bottom. A rocky or coarse sand bottom is not a good place for mushroom anchors (INAMAR, 2000).

Purpose

Without the knowledge of what type of anchor is used and what type of soil material it is set in, the holding capacity of the mooring is compromised. The type of soil material has a great deal to do with the holding power of anchors. This soil interpretation is intended to help identify the type of soil material suitable for mushroom anchors. Soil Ratings

Soils are placed into interpretive rating classes per their rating indices. The rating indices finds the sum of the horizon thicknesses having each n-value condition between 0 and 150 centimeters. The n-value associated with the highest sum of horizon thicknesses is used to place the soil into a rating class. Soils rated for mushroom anchors are either very limited, somewhat limited, not limited, or not rated.

Very Limited: Soils with a low n-value (nonfluid) between 0 and 150 centimeters from the soil surface are rated very limited for mushroom anchors.

Somewhat Limited: Soils with an n-value of slightly or moderately fluid between 0 and 150 centimeters from the soil surface are rated somewhat limited for mushroom anchors.

Not Limited: Soils with a high n-value (very fluid) between 0 and 150 centimeters from the soil surface are rated not limited for mushroom anchors.

Not Rated: Soils or miscellaneous areas that do not have a subaqueous drainage class are not rated.

Reference

INAMAR. 2000. Moorings: important recommendations for safe moorings from INAMAR. p. 1-8.

Agricultural Organic Soil Subsidence

Soil Quality is primarily influenced by human management, which is not captured in soil survey data at this time. These interpretations provide information on inherent soil properties that influence our ability to build healthy soils through management. Organic soils used in agricultural production are subject to a loss of volume and depth of organic material due to oxidation caused by above normal microbial activity resulting from excessive water drainage, soil disturbance, or extended drought. Microbial mediated oxidation is the primary driver of volume reduction once excess water is removed. Soil shrinkage and compaction due to dewatering is considered to be secondary. Any drawdown resulting in water levels below soil surface can result in increased subsidence rates. The subsidence rate can also be influenced by agricultural practices. The type of tillage operation, such as plowing, disc harrowing and switch plowing, moldboard plowing increase the oxidation rate. The use of no-till practice is recommended to slow the subsidence. Any aggressive tillage measure increases microbiological activity and decreases carbon sequestration. Drainage water management can be implemented to control water tables to help slow the subsidence rate.

Several soil and site properties influence the rate of organic matter oxidation and subsidence. Organic soils are generally found in cooler climates, thus, farmed organic soils in warmer climates are vulnerable. Periodic saturation of the organic soil with water tends to decrease the rate of oxidation since anaerobic decomposition is slower than aerobic decomposition. The pre-existing degree of decomposition is also a factor in the subsidence rate since as organic matter is decomposed, the remaining material becomes more resistant to decay. Acidity in soils tends to slow microbial growth so acid soils are less prone to subsidence. The degree to which each of the soil properties considered promotes oxidation is rated. The average degree of accelerating microbial oxidation of organic matter is taken as the overall rating.

The ratings are both verbal and numerical. Numerical ratings indicate the suitability of the individual soil properties. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the most severe propensity for subsidence (1.00) and the point at which the soil has no propensity for subsidence, such as a mineral soil (0.00).

Rating class terms indicate the rate at which the soils are likely to subside considering all the soil features that are examined for this rating. "Severe subsidence" indicates that the soil has features that are very favorable for the aerobic soil organisms that cause subsidence. Very careful management will be needed to slow the subsidence rate. "Moderate subsidence" indicates that the soil has features that are moderately favorable for aerobic soil organisms. The soil can be made more sustainable by careful management. "Low subsidence" indicates that the soil has one or more features that are unfavorable for aerobic soil organisms. With careful management the soil can be used for crop production and be nearly sustainable. Soils that are not organic are rated "Mineral soil". These soils do not subside due to organic matter oxidation.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is being provided for review and comment by the user community. Please forward any feedback to the Soils Hotline soilshotline@lin.usda.gov.

Dynamic Soil Properties Response to Biochar Application

Biochar is the solid byproduct of the decomposition of organic materials in oxygen-limited environments at high temperatures, a process known as known as pyrolysis. The extremely carbon-rich material has an average half-life of 1,400 years, due to its recalcitrant benzene-ring structure, allowing it to sequester carbon in soils over long periods of time, with the potential to provide substantial increases to soil organic matter when applied to soils. Although it has only recently begun to receive attention as a Soil Quality amendment, biochar has been used to increase the fertility, productivity, and health of soils around the world by indigenous communities for thousands of years, most notably in the Amazon rainforest. The feedstock used to produce biochar has a significant impact on its properties. Many waste products can be pyrolized to produce biochar. These include forestry wastes, grass clippings, manure, food wastes, and many other waste products. This interpretation assumes a corn stover and manure waste feedstock, producing a mid-range particle size, ideally sourced locally. In recent years, the number of large-scale biochar producers has increased, lowering the cost of using the material. This interpretation assumes a minimal incorporation with tillage, rather spreading the biochar with a manure surface spreader. Application methods vary. The biochar can be mixed with manure and spread as a part of a slurry.

Soil and site properties can be dynamic (changeable on a human timescale) or more or less use invariant. Dynamic soil properties associated with Soil Quality include pH, cation exchange capacity, water holding capacity, bulk density, hydraulic conductivity, and organic matter content. These properties affect aggregate stability, fungal growth, and microbial activity, which in turn affect plant growth. Conceptually, these properties may be improved by the application of biochar. The degree of improvement of a property is dependent upon how poor the current Soil Quality condition is. Less healthy soils are more likely to be improved than healthy soils. Thus, soils that are already healthy will not be substantively improved with biochar application. Some conditions of the site, such as slope, ponding, flooding, karst, and rock fragment content, while affecting the application and use of biochar, cannot be changed by biochar application.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are suited by all of the soil features that affect these uses. Numerical ratings indicate the degree of suitability of each soil or site feature. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest theoretical positive response of dynamic soil properties to biochar application (1.00) and the point at which the soil and site features indicate that biochar application will not improve dynamic soil properties (0.00).

Verbal ratings are defined as follows:

Excellent response (rating index equals 1.0) One or more dynamic soil properties present are suboptimal for the growth of crops and may be substantially improved with biochar application.

Good response (rating index is greater than 0.75 but less than 1.0) One or more dynamic soil properties present are suboptimal for the growth of crops and may be substantially improved with biochar application. One or more use invariant properties may limit the effectiveness of biochar.

Fair response (rating index is greater than 0.25 but less than 0.75) One or more dynamic soil properties present may already be nearly optimal for the growth of crops and may not be substantially improved with biochar application. One or more use invariant properties may limit the effectiveness of biochar.

Low response (rating index is greater than 0 but less than 0.25). One or more dynamic soil properties present may already be nearly optimal for the growth of crops and may not be substantially improved with biochar application. One or more use invariant properties may limit the effectiveness of biochar, but not preclude its use.

Negligible response (rating index equals 0). The soil is rendered unsuitable for biochar application because the use invariant soil and site properties are limiting to crop production and cannot be overcome. The site may be too steeply sloping, too wet, flooded, or ponded.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References and Resources

Arif, M., Ilyas, M., Riaz, M., Ali, K., Shah, K., Ul Haq, I., Fahad, S. 2017. Biochar improves phosphorus use efficiency of organic-inorganic fertilizers, maize-wheat productivity and soil quality in a low fertility alkaline soil. Field crops research. 214, 25-37.

Bruun, S. and El-Zehery, T. 2012. Biochar effect on the mineralization of soil organic matter. Pesq. Agropec. Bras. Vol 47 (5).

Bu, X. Xue, J. Wu, Y., Ma, W. 2020. Effect of biochar on seed germination and seedling growth of Robinia pseudoacacia L. in karst calcareous soils. Comm. In Soil Science and Plant Analysis. Vol. 51 (3), 352-363.

Burrell, L.D., F. Zehetner, N. Rampazzo, B. Wimmer, and G. Soja. 2016. Long-term effects of biochar on soil physical properties. Geoderma 282:96-102.

CCE of Suffolk County. 2020. Biochar Basics: https://vod.video.cornell.edu/media/1_0zozgaa6

Cheng, C.H., J. Lehmann, and M.H. Engelhard. 2008. Natural oxidation of black carbon in soils: Changes in molecular form and surface charge along a climosequence. Geochimica et Cosmochimica Acta 72:15981610.

Dokoohaki, H., Miguez, F.E., Laird, D., Dumortier, J. 2019. Where should we apply biochar? Environ. Res. Lett. 14 044005.

Fidel, R.B., Laird, D.A., Thompson, M.L., Lawrinenko, M. 2016. Characterization and quantification of biochar alkalinity. Chemosphere. 167, 367-373.

Gunes, A., Inal, A., Taskin, M.B., Sahin, O., Kaya, E.C., Atakol, A.R.D.A. 2014. Effect of phosphorus-enriched biochar and poultry manure on growth and mineral composition of lettuce (Lactuca sativa L. cv.) grown in alkaline soil.

Ibrahim, H.M., Al-Wabel, M.I., Usman, A.R.A., Al-Omran, A. 2013. Effect of Conocarpus biochar application on the hydraulic properties of a sandy loam soil. Soil Science. 178 (4), 165-173.

Kishimoto S. and Sugiura, G. 1985. Charcoal as a soil conditioner. Symposium on Forest Products Research International Achievements for the Future 5, 1223.

Li, G.Z., Zhang C.R., Ibrahim, M., Zhang, G., Wang, L., Zhang, R., Chen, F. and Liu, Y. 2017. The beneficial effect induced by biochar on soil erosion and nutrient loss of sloping land under natural rainfall conditions in central China. Agric. Water Manage. 185:145150. 43.

Liu, Z., Dugan, B., Masiello, C.A., Gonnermann, H.M. 2017. Biochar particle size, shape, and porosity act together to influence soil water properties. PLoS ONE 12(6): e0179079. https://doi.org/10.1371/journal.pone.0179079.

Major, J., Rondon, M., Molina, D., Riha, S.J., Lehmann, J. 2010. Maize yield and nutrition during 4 years after biochar application to a Colombian savanna oxisol. Plant Soil, 333, pp. 117-128

Mukherjee, A., A.R. Zimmerman, and W. Harris. 2011. Surface chemistry variations among a series of laboratory-produced biochars. Geoderma 163:247-255.

Novak, J.M., W.J. Busscher, D.L. Laird, M. Ahmedna, D.W. Watts, and M.A.S. Niandou. 2009. Impact of Biochar Amendment on Fertility of a Southeastern Coastal Plain Soil. Soil Science 174:105-112.

Pituello, C.; Ferro, N. dal; Francisco, O.; Simonetti, G.; Berti, A.; Piccoli, I.; Pisi, A.; Morari, F. Effects of biochar on the dynamics of aggregate stability in clay and sandy clay loam soils. European Journal of Soil Science. 69 (5) Oxford; Wiley, 2019, pp. 827-842.

Silva, F.C., C. Borrego, J.J. Keizer, J.H. Amorim, and F.G.A. Verheijen. 2015. Effects of moisture content on wind erosion thresholds of biochar. Atmospheric Environment 123:121-128.

Vaccari, F.P., Baronti, S., Lugato, E., Genesio, L., Castaldi, S., Fornasier, F. Miglietta, F. 2011. Biochar as a strategy to sequester carbon and increase yield in durum wheat. Eur. J. Agron., 34, pp. 231-238

Zhang, M., Riaz, M., Zhang, L, El-desouki, Z., Jiang, C. 2019. Biochar induces changes to basic soil properties and bacterial communities of different soils to varying degrees at 25 mm rainfall: more effective on acidic soils. Front. Microbiol. 10:1321. doi: 10.3389/fmicb.2019.01321

Composting is a method of using natural processes to change vegetative debris into a useful product. This interpretation evaluates the degree and kind of limitation(s) that affect the siting of a surface composting facility to stabilize vegetative debris produced as a result of typical farming and horticultural practices.

The soil is evaluated from the surface to a depth of 79 inches. The ratings are based on the soil properties that affect trafficability; attenuation of suspended, soil solution, and gaseous decomposition products and microorganisms; construction and maintenance of the site; and public health. Improper site selection, design, or installation may cause contamination of ground water, seepage, and contamination of stream systems from surface drainage or floodwater.

Properties that influence the risk of pollution, ease of excavation, trafficability, and revegetation are major considerations. Soils that flood or have a water table within the depth of excavation present a potential pollution hazard and are difficult to excavate. Soils that have high saturated hydraulic conductivity (Ksat), that are shallow to bedrock, ice, or a cemented pan, or that have a high content of stones and boulders are limited because these features interfere with the installation, performance, and maintenance of the system. Slope is an important consideration because it affects the work involved in road construction, the performance of the roads, and the control of surface water around the facility.

Climatic factors influence the ease with which a composting facility can be maintained. Adequate precipitation to keep the mass moist, and sufficient heat to sustain biological activity are essential.

The ratings are both verbal and numerical. Numerical ratings indicate the severity of the individual limitations. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest limitation on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect these uses. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected of a properly designed and installed system on these soils. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Soils can be rated based on their susceptibility to degradation in the "Fragile Soil Index" interpretation. Fragile soils are those that are most vulnerable to degradation. In other words, they can be easily degradedthey have a low resistance to degradation processes. They tend to be highly susceptible to erosion and can have a low capacity to recover after degradation has occurred (low resilience). Fragile soils are generally characterized by a low content of organic matter, low aggregate stability, and weak soil structure. They are generally located on sloping ground, have sparse plant cover, and tend to be in arid or semiarid regions. The index can be used for conservation and watershed planning to assist in identifying soils and areas highly vulnerable to degradation.

Depending on inherent soil characteristics and the climate, soils can vary from highly resistant, or stable, to vulnerable and extremely sensitive to degradation. Under stress, fragile soils can degrade to a new altered state, which may be less favorable or unfavorable for plant growth and less capable of performing soil functions. To assess the fragility of the soil, indicators of vulnerability to degradation processes are used. They include organic matter, soil structure, rooting depth, vegetative cover, slope, and aridity.

The organic matter content indicates the capacity of the soil to resist and/or recover from degradation processes. Organic matter improves the soil pore structure, increases water infiltration, and reduces soil compaction and soil erosion. Soil structure indicates the capacity of the soil to resist degradation from accelerated water erosion (by increasing the amount of infiltration). Pore structure is the most important aspect of soil structure as pores provide habitat for organism. Shallow soils are more vulnerable to degradation processes because they have limited rooting depth and have a reduced amount of material from which to form new soil. As erosion removes the upper soil profile, productivity will decline if the subsoil is limiting for crop growth. Vegetative cover is very important as uncovered soil is most vulnerable to the processes of soil erosion, both by wind and water. Slope (a measure of the steepness or the degree of inclination) indicates the degree of vulnerability to erosion and mass movement. Aridity is defined by the shortage of moisture. Lack of water is a main factor limiting biological processes and the ability of the soil to resist and/or recover from degradation.

Soils are placed into interpretive classes based on their index rating, which ranges from 0 to 1. An index rating of 1 is the most fragile, while a rating of zero is the least fragile. Interpretative classes are as follows:

Not Fragile (index rating less than or equal to 0.009) These soils have a very high potential to resist degradation and be highly resilient. They are highly structured with an organic matter content greater than 5.7%, are nearly level, are deep or very deep, have greater than 85% vegetative cover, and are in a climate that is wet or very wet.

Slightly Fragile (index rating less than 0.009 and less than or equal to 0.209) These soils have a high potential to resist degradation and be resilient. They are: -- Poorly structured to weakly structured soils that have an extremely low to moderate content of organic matter, are very deep, have high vegetative cover, occur on nearly level ground, and are in wet or very wet climates; -- Highly structured soils that have a very high content of organic matter, are very shallow to moderately deep, have high vegetative cover, occur on nearly level ground, and are in wet or very wet climates; -- Highly structured soils that have a very high content of organic matter, are very deep, have low to moderately high vegetative cover, occur on nearly level ground, and are in wet or very wet climates; -- Highly structured soils that have a very high content of organic matter, are very deep, have high vegetative cover; are on slopes greater than 3%, and are in wet or very wet climates; or -- Highly structured soils that have a very high content of organic matter, are very deep, have high vegetative cover; occur on nearly level ground, and in semi-dry to mildly wet climates;

Moderately Fragile (index rating greater than 0.209 and less than or equal to 0.409) These soils have a moderate potential to resist degradation and be moderately resilient. They are: -- Highly structured soils that have a very high content of organic matter, are very shallow, have high vegetative cover, occur in nearly level to moderately sloping areas, and are in semi-dry climates; -- Poorly structured soils that have an extremely low content of organic matter, are deep, have low vegetative cover, occur in nearly level areas, and are in wet or very wet climates; -- Poorly structured soils that have an extremely low content of organic matter, occur on gentle to very steep slopes, have high vegetative cover, and are in wet or very wet climates; -- Weakly structured soils that have a very low content of organic matter, are deep, occur in nearly level to gently sloping areas, have high vegetative cover, and are in semi-dry climates; or -- Weakly structured soils that have a very low content of organic matter, are very shallow to very deep, occur in nearly level to strongly sloping areas, have high vegetative cover, and are in mildly wet climates.

Fragile (index rating greater than 0.409 and less than or equal to 0.609) These soils have a low potential to resist degradation and low resilience. They are: -- Well structured soils that have a low content of organic matter, are shallow to very deep, have moderate to moderately high vegetative cover, occur on steep slopes, and are in dry climates; -- Well structured soils that have a low content of organic matter, are shallow to very deep, have a low vegetative cover, occur in nearly level to gently sloping areas, and are in dry climates; -- Well structured soils that have a low content of organic matter, are deep, have low vegetative cover, occur on nearly level to very steep slopes, and are in a semi-dry climate; -- Moderately structured soils that have a very low content of organic matter, are deep, have moderately high vegetative cover, occur on moderately steep to very steep slopes, and are in semi-dry climates; or -- Weakly structured soils that have a low content of organic matter, occur on moderately steep to very steep slopes, have low vegetative cover, and are in wet or very wet climates.

Very Fragile (index rating greater than 0.609 and less than or equal to 0.809) These soils have a very low potential to resist degradation and very low resilience. They are: -- Weakly structured soils that have an extremely low content of organic matter, are deep, have low vegetative cover, occur on nearly level to very steep slopes, and are in dry climates; -- Weakly structured soils that have an extremely low content of organic matter, are shallow to very deep, have low vegetative cover, occur on nearly level to very steep slopes, and are in very dry climates; or -- Poorly structured soils that have an extremely low content of organic matter, are very shallow, have no vegetative cover, occur on steep slopes, and are in mildly wet to wet climates.

Extremely Fragile (index rating greater than 0.809 and less than or equal to 1.0) These soils can have no potential to resist degradation and no resilience. They are: -- Poorly structured soils that have an extremely low content of organic matter, are very shallow, have low vegetative cover, occur on very steep slopes, and are in dry or very dry climates; -- Weakly structured soils that have a very low content of organic matter, are nearly level to very deep, have low vegetative cover, occur on very steep slopes, and are in dry climates; or -- Very shallow soils on steep slopes.

The interpretive rating is based on soils that occur in the dominant land use for the map unit component and may not represent soils that occur in site-specific land uses.

Inherent Limitation for Aerobic Soil Organisms

Soil Quality is primarily influenced by human management, which is not captured in soil survey data at this time. These interpretations provide information on inherent soil properties that influence our ability to build healthy soils through management. Soil is the habitat for a wide variety of organisms, ranging from microscopic viruses, bacteria, archaea, fungi, and protozoa to micro- and meso-fauna including nematodes, mites, and springtails to macrofauna such as earthworms, centipedes and beetles to name just a few. A healthy soil is a living system that supports an abundant and diverse biological community that aids crop production by providing key services and functions. These include: 1) the decomposition of organic materials and conversion into soil organic matter; 2) enhanced nutrient cycling; 3) improved soil structure and stability that positively influences water flow, storage and availability; 4) plant protection against disease, pests, and environmental stress; and, 5) detoxification of pollutants. Soil microbes are generally most abundant in the surface layer around plant roots (termed the rhizosphere). Soils vary in their inherent ability to foster plant growth and thus also in their ability to support microbial populations. Although bacteria and archaea possess alternative metabolic strategies to survive under low or no oxygen content (i.e., anaerobic conditions), all other soil organisms require oxygen and the majority of soil bacteria in agricultural soils function more efficiently in aerobic conditions. therefore, only aerobic organisms are considered.

Several site and soil properties contribute to major attributes in the suitability for aerobic organisms. Those chosen for this table include: Soil temperature, since most biological processes increase, often double, with a 10C increase in temperature; water, inferred through the average total yearly precipitation since plant productivity is linked to precipitation and soil microbes thrive in the rhizosphere; soil organic matter content as organic carbon is required by many soil organisms as an energy and carbon source; soil pore space influences water and gas movement as well as physical space for organisms to occupy and the tortuosity of paths through which they may move; soil water content is important as when too much water is present anaerobic processes begin and shifts the population to anaerobic bacteria and when too little is present organisms may die or go dormant; and, osmotic conditions are also important, as are the presence of toxic materials or the absence of required elements.. The degree of favorability of each of these properties is rated for a soil and the degree of limitation of the least favorable attribute determines the overall rating. The ratings are both verbal and numerical. Numerical ratings indicate the suitability of the individual soil properties. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest favorability for organisms (1.00) and the point at which the soil feature becomes not favorable (0.00).

Rating class terms indicate the extent to which the soils are favorable considering all the soil features that are examined for this land use. "Very favorable" indicates that the soil has features that are very favorable for aerobic soil organisms. Healthy and thriving populations can be expected on properly managed agricultural systems on these soils. "Somewhat favorable" indicates that the soil has features that are moderately favorable for aerobic soil organisms. The soil can be made more favorable by careful management. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for aerobic soil organisms.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is being provided for review and comment by the user community. Please forward any feedback to the Soils Hotline soilshotline@lin.usda.gov.

References Blanco-Canqui, H., M.M. Mikha, D.R. Presley, and M.M. Claassen. 2011. Addition of cover crops enhances no-till potential for improving soil physical properties. Soil Sci. Soc. Am. J. 75:14711482. doi:10.2136/ sssaj2010.0430. Carr, B. 2015. Winter Cover Crop Species Adapted to North-Central West Texas and Southwestern Oklahoma. National Cooperative Soil Survey James E. Bud Smith Plant Material Center. Knox City, TX. June 2015. 8p. ID# 12635. Duiker, 2014. Effects of Soil Compaction. Penn State Extension.

Fernandez-Calvino, D., E. Baath. 2010. Growth response of the bacterial community to pH in soils differing in pH. FEMS Microbiol Ecol 73 (2010) 149156.

Fierer, N., and R.B. Jackson. 2006. The diversity and biogeography of soil bacterial communities. Proceedings of the National Academy of Sciences of the United States of America 103:626-631.

Hooper D. U., Bignell D. E., Brown V. K., Brussaard, L. 2000. Interactions between aboveground and belowground biodiversity in terrestrial ecosystems: Patterns, mechanisms, and feedbacks. Bioscience 50 (12):1049-1061.

Kemper W. D., and E.J. Koch. 1966. Aggregate stability of soils from western United States and Canada. Technical Bulletin No. 1355. United States Department of Agriculture Agricultural Research Service. U S Government Printing Office Washington, DC. pp 52.

Kieft, T.L., Soroker, ED., and M. Firestone. Microbial Biomass response to rapid increase in water potential when dry soil is wetted. Soil Biology and Biochemistry, Soil &of. Biochem. Vol. 19. No. 2, pp. I 19-I 26, 1987. Lauber, C.L., M. Hamady, R. Knight, and N. Fierer. 2009. Pyrosequencing-based assessment of soil pH as a predictor of soil bacterial community structure at the continental scale. Applied and Environmental Microbiology 75:5111-5120.

Olson, Kenneth, Ebelhar S. E., and James M. Lang. 2014. Long-Term Effects of Cover Crops on Crop Yields, Soil Organic Carbon Stocks and Sequestration. Open Journal of Soil Science Vol.04No.08:9. doi: 10.4236/ojss.2014.48030. Owojori, O. J., A. J. Reinecke, P. Voua-Otomo, and S. A. Reinecke. 2009. Comparative study of the effects of salinity on life-cycle parameters of four soil-dwelling species (Folsomia candida, Enchytraeus doerjesi, Eisenia fetida and Aporrectodea caliginosa). Pedobiologia 52 (6):351-360. doi: https://doi.org/10.1016/j.pedobi.2008.12.002.

Porazinska D. L., Bardgett R.D., Blaauw M.B., Hunt W.H., Parsons A.N., Seastedt T.R., and Wall, D.H. 2003. Relationships at the Aboveground-belowground interface: Plants, Soil Biota, and Soil Processes. Ecological Monographs 73 (3):377-395. doi: 10.1890/0012-9615(2003)073[0377:RATAIP]2.0.CO;2.

Schenk, H.R., R.B. Jackson. Rooting depths, lateral root spreads and below-ground/above-ground allometries of plants in water-limited ecosystems. Journal of Ecology. Volume 90, Issue 3. June 2002. Pages 480494. U.S. Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2008. Soil Quality Indicators. National Cooperative Soil Survey Publication.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2014. Soil Quality Kit - Guide for Educators. Bulk Density, Moisture, Aeration. National Cooperative Soil Survey Publication.

Soil Organic Matter Depletion

Soil Quality is primarily influenced by human management, which is not captured in soil survey data at this time. These interpretations provide information on inherent soil properties that influence our ability to build healthy soils through management.

A fertile and healthy soil is the basis for healthy plants, animals, and humans. Soil organic matter is the very foundation for healthy and productive soils. Understanding the role of organic matter in maintaining a healthy soil is essential for developing ecologically sound agricultural practices. Perhaps just as important is identifying areas at greater risk of organic matter depletion. For organic matter to accumulate in soil, the processes that synthesize organic matter generally need to be greater than the processes that destroy organic matter. These processes occur at continental and local scales. Continental-scale factors include the mean annual temperature, which ultimately governs the rates of biological processes, including both the synthesizing and destroying of organic matter. Another continental-scale factor is the amount of water generally available for use by plants and soil microbes. The amount of available water is governed by the amount of rainfall or snowmelt that an area receives in relation to evapotranspiration. This interpretation does not take into account the application of irrigation water.

The continental-scale factors are modified by local factors. Oxygen is needed for both the accumulation and destruction of organic matter. It can be excluded from the soil by seasonal saturation, which generally favors the accumulation processes. The antecedent organic matter content is used as an indicator of the level of a soils vulnerability to loss of organic matter. In general, well aerated soils tend to have higher oxidation rates but may still accumulate organic matter, depending on other factors, such as ground cover, length of time that living roots are present in the soil, and management practices. Clay-sized particles in the soil help protect organic compounds and so tend to favor organic matter accumulation. The shape of the land surface also influences the organic matter content. Water and sediment tend to accumulate in concave areas while material tends to disperse in convex areas. The degree of limitation caused by each of these properties is rated for a soil and the sum of the ratings is the overall rating. The ratings are both verbal and numerical. Numerical ratings indicate the propensity of the individual soil properties to influence organic matter degradation. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest ability to enable organic carbon depletion (1.00) and the point at which the soil feature becomes least likely to allow organic matter depletion (0.00).

Rating class terms indicate the extent to which the soils enable the depletion of organic matter. "Organic matter depletion high" indicates that the soil and site have features that are very conducive to the depletion of organic matter. Very careful management will be needed to prevent serious organic matter loss when these soils are farmed. "Organic matter depletion moderately high", "Organic matter depletion moderate", and "Organic matter depletion moderately low" are a gradient of the level of management needed to avoid organic matter depletion. "Organic matter depletion low" indicates soils that have features that are favorable for organic matter accumulation. These soils allow more management options while still maintaining favorable organic matter levels.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is being provided for review and comment by the user community. Please forward any feedback to the Soils Hotline soilshotline@lin.usda.gov.

References

Owens, P., E. Winzeler, Z. Libohova, S. Waltman, D. Miller, and B. Waltman. Evaluating U.S. Soil Taxonomy soil climate regimes: Application across scales. https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_053084.pdf (accessed 1 March 2018).

Page-Dumrose, D.S. 1993. Susceptibility of volcanic ash-influenced soils in northern Idaho to mechanical compaction. U.S. Forest Service Intermountain Research Station. Research Note INT-409.

Pimentel, D. 2006. Soil erosion: A food and environmental threat. Environment, Development and Sustainability 8:119-137.

Schmitt, A., and B. Glaser. 2011. Organic matter dynamics in a temperate forest as influenced by soil frost. Journal of Plant Nutrition and Soil Science 174(5):754764. https://doi.org/10.1002/jpln.201100009.

Schmidt, M.W.I., M.S. Torn, S. Abiven, T. Dittmar, G. Guggenberger, I.A. Janssens, and S.E. Trumbore. 2011. Persistence of soil organic matter as an ecosystem property. Nature 478:49-56. http://dx.doi.org/10.1038/nature10386.

Soil Survey Staff. 2014. Keys to Soil Taxonomy, 12th edition. Natural Resources Conservation Service, Washington, DC. https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/class/taxonomy/?cid=nrcs142p2_053580.

U.S. Department of Agriculture, Agricultural Research Service. 1997. Predicting soil erosion by water: A guide to conservation planning with the Revised Universal Soil Loss Equation (RUSLE). Agriculture Handbook 703. https://www.ars.usda.gov/ARSUserFiles/64080530/rusle/ah_703.pdf.

U.S. Department of Agriculture, Natural Resources Conservation Service. National Soil Survey Handbook, Title 430-VI. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_054242 (accessed 1 March 2018).

U.S. Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf (accessed 1 March 2018).

Zhanyu, Z., L. Sheng, J. Yang, X.-A. Chen, L. Kong, and B. Wagan. 2015. Effects of land use and slope gradient on soil erosion in a red soil hilly watershed of southern China. Sustainability 7(10):14309-14325; doi:10.3390/su71014309.

Soil Quality is primarily influenced by human management, which is not captured in soil survey data at this time. This interpretation provides information on inherent soil properties that influence our ability to build healthy soils through management.

Surface sealing is the orientation and packing of dispersed soil particles that result from the physical breakup of soil aggregates due to raindrop impact. Rapid soil wetting (in dry soils) and high exchangeable sodium percent can also cause aggregates to disperse. Sealing results when clay and silt particles get detached and/or dispersed and become suspended in the infiltrating water, which is moving downward through surface-connected pores. The pores become clogged with the fine particles, which become closely packed and create a surface seal.

Surface sealing is the initial process in the formation of a mineral crust, which is a broader term for a surface feature that is dense, hard, or restricts infiltration. A seal is a more specific term and refers to a surface layer that inhibits infiltration (Heil, 1993).

Significance:

The presence of a soil surface seal indicates poor Soil Quality. Surface seals affect crop production by inhibiting seedling emergence, decreasing the infiltration rate, reducing the amount of available water to plants, and increasing runoff and erosion. They also diminish the natural recharge of aquifers (Assouline, 2011) and reduce aeration, and so affect several metabolic processes of micro and macro flora and fauna in the soil (Igwe and Udegbunam, 2008). Surface sealing has also been shown to be the primary cause of post-fire runoff and erosion (Larsen et al., 2007).

Factors Affecting Surface Sealing:

The intensity and energy of rainfall is an important factor affecting the susceptibility of a soil to form a seal (Moncada et al., 2014). Under most conditions and given enough time, most non-swelling bare soils will become impermeable to water because of clogging of surface pores (Heil, 1993). In swelling soils, the formation of surface seals occurs in the zone between the cracks (until the cracks close), thus limiting infiltration to the vicinity of the crack (Wells et al., 2003).

Inherent factors.The tendency of a soil to form a seal depends on the stability of aggregates. Soils that are highly susceptible to surface sealing have low organic matter contents, are high in silt relative to clay and organic matter, and/or have weak aggregation where a high percentage of the clay disperses easily in water. Dispersion can also result from a high content of exchangeable sodium. Organic matter or Fe and Al oxides are important agents in the formation of stable aggregates. When the number of these agents is low, soils are more susceptible to aggregate breakup and surface sealing.

Dynamic factors.Management that protects the soil from raindrop impact and minimizes soil disturbance helps prevent surface sealing. Plant and mulch cover can shield the soil from raindrop impact and so reduce sealing in otherwise susceptible soils. Soil management practices that increase organic matter combined with the use of plant or residue cover for protection help prevent the formation of surface seals in most soils. Because tillage disrupts soil structure and aggregates, it accelerates the formation of seals. Management that minimizes soil disturbances and protects the soil from raindrop impact greatly increases infiltration and reduces runoff.

Interpretation Summary:

This interpretation is applicable to conditions or times when the soil surface, or any portion of it, is exposed to the impact of raindrops and there is significant rain or sprinkler irrigation. Soil surfaces that are void of vegetative, canopy, residue, litter, or duff cover are the most vulnerable to surface sealing.

Soils are rated based on the collective susceptibility of their properties to surface sealing. Ratings are on a scale from 0.0 to 1.0. If a soil's property within the surface layer has an index value greater than 0.0, then that soil property is limiting and contributes to the soils susceptibility to surface sealing. The overall interpretive rating assigned is the maximum index value for one or more of the soil interpretive properties that comprise the Soil Surface Sealing interpretation. These properties include exchangeable sodium, a silt/crusting index, water dispersible clay, and organic matter. Soils are placed into interpretive rating classes per their rating indices. These classes are low susceptibility (rating index = 0), moderate susceptibility (rating index greater than 0 and less than 1), and high susceptibility (rating index = 1).

This interpretation is being provided for review and comment by the user community. Please forward any feedback to the Soils Hotline (soilshotline@lin.usda.gov).

References:

Assouline, S. 2011. Soil surface sealing and crusting. In: J. Glinski, J. Horabik, and J. Lipiec (eds.) Encyclopedia of agrophysics: Encyclopedia of earth sciences series. Springer, Dordrecht, The Netherlands. pp. 786-791.

Heil, J.W. 1993. Soil properties influencing hydraulic sealing of the surface on Alfisols in the Sahel. Doctoral dissertation, Texas A&M University. College Station, Texas.

Igwe, C.A., and O.N. Udegbunam. 2008. Soil properties influencing water-dispersible clay and silt in an Ultisol in southern Nigeria. International Agrophysics 22:319-325.

Larsen, I.J., L.H. MacDonald, E. Brown, D. Rough, M.J. Welsh, J.H. Pietraszek, Z. Libohova, J. de Dios Benavides-Sororio, and K. Schaffrath. 2007. Causes of post-fire runoff and erosion: Water repellency, cover, or soil sealing? Soil Science Society of America Journal 73:1393-1407.

Moncada, M.P., D. Gabriels, D. Lobo, K. De Beuf, R. Figueroa, and W.M. Cornelis. 2014. A comparison of methods to assess susceptibility to soil sealing. Geoderma 226-227:397-404.

Wells, R.R., D.A. DiCarlo, T.S. Steenhuis, J.-Y. Parlange, M.J.M. Romkens, and S.N. Prasad. 2003. Infiltration and surface geometry features of a swelling soil following successive simulated rainstorms. Soil Science Society of America Journal 67:1344-1351.

Soils are rated based on their susceptibility to compaction from the operation of ground-based equipment for planting, harvesting, and site preparation activities when soils are moist. Soil compaction is the process in which soil particles are pressed together more closely that in the original state. Typically, the soil must be moist to be compacted because the mineral grains must slide together. Compaction reduces the abundance mostly of large pores in the soil by damaging the structure of the soil. This produces several effects that are unwanted in agricultural soils since large pores are most effective at transmitting water and air through the soil. Compaction also increases the soil strength which can limit root penetration and growth. The ability of soil to hold water is adversely affected by compaction since the large pores hold water. The degree of compaction of a soil is measured by its bulk density, which is the mass per unit volume, generally expressed in grams per cubic centimeter.

Compacted soils are less favorable for good plant growth because of high soil bulk density and hardness, reduced pore space, and poor aeration and drainage. Root penetration and growth is decreased in compacted soils because the hardness or strength of these soils prevents the expansion of roots. Supplies of air, water, and nutrients that roots need are also less favorable when compaction decreases soil porosity and drainage.

Interpretation ratings are based on soil properties in the upper 12 inches of the profile. Factors considered are soil texture, soil organic matter content, soil structure, rock fragment content, and the existing bulk density. Each of these is thought to contribute to resisting the susceptibility of a soil to compaction when present. Organic matter in the soil provides resistance to compaction and the resilience to ameliorate the effects with time. Soil structure adds strength as discrete aggregates and it is the aggregates that are deformed or destroyed by compactive forces, thus strong soil structure lowers the susceptibility to compaction. Similarly, rock fragments in the soil can bridge and provide a framework to resist compaction. Finally, if a soil is already fairly dense causing further compaction is more difficult.

Definitions of the ratings:

Low - The potential for compaction is insignificant. This soil is able to support standard equipment with minimal compaction. The soil is moisture insensitive, exhibiting only small changes in density with changing moisture content.

Medium - The potential for compaction is significant. The growth rate of seedlings may be reduced following compaction. After the initial compaction (i.e., the first equipment pass), this soil is able to support standard equipment with only minimal increases in soil density. The soil is intermediate between moisture insensitive and moisture sensitive.

High - The potential for compaction is significant. The growth rate of seedlings will be reduced following compaction. After initial compaction, this soil is still able to support standard equipment, but will continue to compact with each subsequent pass. The soil is moisture sensitive, exhibiting large changes in density with changing moisture content.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References:

Adams, P.W. 1998. Soil Compaction on Woodland Properties. Oregon State University Extension Publication EC 1109.

Adams, P.W. 1981. Compaction of Forest Soils. Oregon State University Extension Publication PNW 217.

Boyer, Don. 1997. Guidelines for Soil Resource Protection and Restoration for Timber Harvest and Post-Harvest Activities. U.S Forest Service, Pacific Northwest Region, Watershed Management.

Geist, J.M.; Hazard, J.W.; Seidel, K.W. 1989. Assessing Physical Conditions of Some Pacific Northwest Volcanic Ash Soils After Forest Harvest. Soil Science Society of America Journal 53:946-950.

Froehlich, Henry A and David H. McNab. 1983. Minimizing Soil Compaction in Pacific Northwest Forests. Proceedings of Sixth North American Forest Soils Conference, University of Tennessee.

Page-Dumrose, Deborah S. 1993. Susceptibility of Volcanic Ash Influenced Soils in Northern Idaho to Mechanical Compaction. U.S. Forest Service Intermountain Research Station. Research Note INT-409.

Inherent Suitability for Aerobic Soil Organisms

Soil Quality is primarily influenced by human management, which is not captured in soil survey data at this time. These interpretations provide information on inherent soil properties that influence our ability to build healthy soils through management. Soil is the habitat for a wide variety of organisms, ranging from microscopic viruses, bacteria, archaea, fungi, and protozoa to micro- and meso-fauna including nematodes, mites, and springtails to macrofauna such as earthworms, centipedes and beetles to name just a few. A healthy soil is a living system that supports an abundant and diverse biological community that aids crop production by providing key services and functions. These include: 1) the decomposition of organic materials and conversion into soil organic matter; 2) enhanced nutrient cycling; 3) improved soil structure and stability that positively influences water flow, storage and availability; 4) plant protection against disease, pests, and environmental stress; and, 5) detoxification of pollutants. Soil microbes are generally most abundant in the surface layer around plant roots (termed the rhizosphere). Soils vary in their inherent ability to foster plant growth and thus also in their ability to support microbial populations. Although bacteria and archaea possess alternative metabolic strategies to survive under low or no oxygen content (i.e., anaerobic conditions), all other soil organisms require oxygen and the majority of soil bacteria in agricultural soils function more efficiently in aerobic conditions. therefore, only aerobic organisms are considered.

Several site and soil properties contribute to major attributes in the suitability for aerobic organisms. Those chosen for this table include: Soil temperature, since most biological processes increase, often double, with a 10C increase in temperature; water, inferred through the average total yearly precipitation since plant productivity is linked to precipitation and soil microbes thrive in the rhizosphere; soil organic matter content as organic carbon is required by many soil organisms as an energy and carbon source; soil pore space influences water and gas movement as well as physical space for organisms to occupy and the tortuosity of paths through which they may move; soil water content is important as when too much water is present anaerobic processes begin and shifts the population to anaerobic bacteria and when too little is present organisms may die or go dormant; and, osmotic conditions are also important, as are the presence of toxic materials or the absence of required elements.. The degree of favorability of each of these properties is rated for a soil and the degree of limitation of the least favorable attribute determines the overall rating. The ratings are both verbal and numerical. Numerical ratings indicate the suitability of the individual soil properties. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest favorability for organisms (1.00) and the point at which the soil feature becomes not favorable (0.00).

Rating class terms indicate the extent to which the soils are favorable considering all the soil features that are examined for this land use. "Very favorable" indicates that the soil has features that are very favorable for aerobic soil organisms. Healthy and thriving populations can be expected on properly managed agricultural systems on these soils. "Somewhat favorable" indicates that the soil has features that are moderately favorable for aerobic soil organisms. The soil can be made more favorable by careful management. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for aerobic soil organisms.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is being provided for review and comment by the user community. Please forward any feedback to the Soils Hotline soilshotline@lin.usda.gov.

References Blanco-Canqui, H., M.M. Mikha, D.R. Presley, and M.M. Claassen. 2011. Addition of cover crops enhances no-till potential for improving soil physical properties. Soil Sci. Soc. Am. J. 75:14711482. doi:10.2136/ sssaj2010.0430. Carr, B. 2015. Winter Cover Crop Species Adapted to North-Central West Texas and Southwestern Oklahoma. National Cooperative Soil Survey James E. Bud Smith Plant Material Center. Knox City, TX. June 2015. 8p. ID# 12635. Duiker, 2014. Effects of Soil Compaction. Penn State Extension.

Fernandez-Calvino, D., E. Baath. 2010. Growth response of the bacterial community to pH in soils differing in pH. FEMS Microbiol Ecol 73 (2010) 149156.

Fierer, N., and R.B. Jackson. 2006. The diversity and biogeography of soil bacterial communities. Proceedings of the National Academy of Sciences of the United States of America 103:626-631.

Hooper D. U., Bignell D. E., Brown V. K., Brussaard, L. 2000. Interactions between aboveground and belowground biodiversity in terrestrial ecosystems: Patterns, mechanisms, and feedbacks. Bioscience 50 (12):1049-1061.

Kemper W. D., and E.J. Koch. 1966. Aggregate stability of soils from western United States and Canada. Technical Bulletin No. 1355. United States Department of Agriculture Agricultural Research Service. U S Government Printing Office Washington, DC. pp 52.

Kieft, T.L., Soroker, ED., and M. Firestone. Microbial Biomass response to rapid increase in water potential when dry soil is wetted. Soil Biology and Biochemistry, Soil &of. Biochem. Vol. 19. No. 2, pp. I 19-I 26, 1987. Lauber, C.L., M. Hamady, R. Knight, and N. Fierer. 2009. Pyrosequencing-based assessment of soil pH as a predictor of soil bacterial community structure at the continental scale. Applied and Environmental Microbiology 75:5111-5120.

Olson, Kenneth, Ebelhar S. E., and James M. Lang. 2014. Long-Term Effects of Cover Crops on Crop Yields, Soil Organic Carbon Stocks and Sequestration. Open Journal of Soil Science Vol.04No.08:9. doi: 10.4236/ojss.2014.48030. Owojori, O. J., A. J. Reinecke, P. Voua-Otomo, and S. A. Reinecke. 2009. Comparative study of the effects of salinity on life-cycle parameters of four soil-dwelling species (Folsomia candida, Enchytraeus doerjesi, Eisenia fetida and Aporrectodea caliginosa). Pedobiologia 52 (6):351-360. doi: https://doi.org/10.1016/j.pedobi.2008.12.002.

Porazinska D. L., Bardgett R.D., Blaauw M.B., Hunt W.H., Parsons A.N., Seastedt T.R., and Wall, D.H. 2003. Relationships at the Aboveground-belowground interface: Plants, Soil Biota, and Soil Processes. Ecological Monographs 73 (3):377-395. doi: 10.1890/0012-9615(2003)073[0377:RATAIP]2.0.CO;2.

Schenk, H.R., R.B. Jackson. Rooting depths, lateral root spreads and below-ground/above-ground allometries of plants in water-limited ecosystems. Journal of Ecology. Volume 90, Issue 3. June 2002. Pages 480494. U.S. Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2008. Soil Quality Indicators. National Cooperative Soil Survey Publication.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2014. Soil Quality Kit - Guide for Educators. Bulk Density, Moisture, Aeration. National Cooperative Soil Survey Publication.

Concentration of Salts- Soil Surface Soil Quality is primarily influenced by human management, which is not captured in soil survey data at this time. These interpretations provide information on inherent soil properties that influence our ability to build healthy soils through management.

Salts of sodium, calcium, potassium, and magnesium are produced by the weathering of minerals in soils. Some salts can be added to the surface due to aeolian deposition. Excess salts can be concentrated in soils when precipitation is sufficient to move salts within the soil but of insufficient quantity to move the salts out of the soil. Salts move downward with percolating precipitation from the generally convex recharge areas of the landscape to the generally concave discharge areas. Net water movement can be upward in these areas due to evapotranspiration or water movement may be more or less horizontal due to restrictive layers or differences in water transmission rates. Excessive salt concentration in the surface of soil is detrimental to the germination and growth of crops due to the osmotic effects of the ions. Several soil and site properties influence the movement and distribution of salts on the landscape. Excess salts must exist in the soil in order to have movement and surface concentration. The concentration of excess salts in soils is estimated by measuring the electrical conductivity of the soil. The soil must exist in a non-leaching environment. In areas where salt accumulates in the soil, precipitation does not exceed evapotranspiration, thus excess salts do not move vertically or laterally through the soil profile and then into ground or surface waters. The soil surface and subsurface must generally concentrate water flow. Research has shown that in regions where rainfall is limited the concave parts of the landscape also concentrate subsurface water flow as well as surface flow. Salts move through soil when water flows. Most water movement happens when the soil is saturated, thus, the depth to saturation and its temporal persistence influence whether or not salts will remain deep in the profile or be carried to the surface. If the water table remains deep the salts will accumulate deeper in the profile. If the water table is close enough to the surface that capillary rise and evapotranspiration can bring water to the soil surface, salts will accumulate at the surface. The degree to which each of the soil properties considered promotes accumulation of surface salts is rated. The rating of the attribute that contributes the least to surface salinization is taken as the overall rating.

The ratings are both verbal and numerical. Numerical ratings indicate the contributions of the individual soil properties. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the most severe propensity for surface salinization (1.00) and the point at which the soil has no propensity for surface salinization (0.00).

Rating class terms indicate the rate at which the soils are likely to subside considering all the soil features that are examined for this rating. "High surface salinization risk or already saline" indicates that the soil has features that are very favorable for the accumulation of salts at the surface or are already saline. These soils are already limited by excess surface salts. "Surface salinization risk" indicates that the soil has features that are somewhat favorable for surface salinization. Careful management will be needed to avoid damage from salinity. "Low surface salinization risk" indicates that the soil has one or more features that are unfavorable for salinization. These soils exist in climates where salinization does not occur or on landscape positions where salts are unlikely to accumulate.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

This interpretation is being provided for review and comment by the user community. Please forward any feedback to the Soils Hotline soilshotline@lin.usda.gov.

Fencing is the construction and maintenance of barriers for the management of animals and people. Metal or wooden posts are used when the fences are built. This interpretation is applicable where the posts are set to a depth of 24 inches or less in the soil and strands of wire are suspended between the posts.

Ratings are based on the ease of setting posts in the soil, the ease of maintaining the wire tension, and the estimated replacement and maintenance costs. Excavations for wooden posts are made by power augers or are hand dug. Metal posts are driven into the soil. Depth to bedrock or a cemented pan and the content of large and small stones influence the excavation of postholes and the driving of posts. Flooding and the depth to a seasonal high water table may restrict the season of construction. Flooding also increases maintenance and replacement costs. High water tables increase maintenance costs and require deeper post settings. In areas of soils that have a high shrink-swell potential, deep post settings or rock jacks are needed to maintain vertical post alignment. Setting the posts in permanently frozen soil may result in loss of the insulation qualities of the soil and in thermokarst topography. In areas of sandy soils, aligning the posts and maintaining the desired wire tension commonly are difficult because of low soil strength. Soil blowing causes maintenance problems. Frost action results in frost heaving of the posts. Steep slopes restrict the use of power augers and the delivery of supplies. On steep slopes, surface creep during wet periods increases maintenance costs. Soil reaction and salinity affect the type of post selected and increase maintenance costs.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

Fencing is the construction and maintenance of barriers for the management of animals and people. Metal or wooden posts are used when the fences are built. This interpretation is applicable where the posts are set to a depth of 36 inches or less in the soil and strands of wire are suspended between the posts.

Ratings are based on the ease of setting posts in the soil, the ease of maintaining the wire tension, and the estimated replacement and maintenance costs. Excavations for wooden posts are made by power augers or are hand dug. Metal posts are driven into the soil. Depth to bedrock or a cemented pan and the content of large and small stones influence the excavation of postholes and the driving of posts. Flooding and the depth to a seasonal high water table may restrict the season of construction. Flooding also increases maintenance and replacement costs. High water tables increase maintenance costs and require deeper post settings. In areas of soils that have a high shrink-swell potential, deep post settings or rock jacks are needed to maintain vertical post alignment. Setting the posts in permanently frozen soil may result in loss of the insulation qualities of the soil and in thermokarst topography. In areas of sandy soils, aligning the posts and maintaining the desired wire tension commonly are difficult because of low soil strength. Soil blowing causes maintenance problems. Frost action results in frost heaving of the posts. Steep slopes restrict the use of power augers and the delivery of supplies. On steep slopes, surface creep during wet periods increases maintenance costs. Soil reaction and salinity affect the type of post selected and increase maintenance costs.

The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected.

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00).

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented.

Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

The purpose of this interpretation is to evaluate the potential for Utah juniper (Juniperus osteosperma) to encroach into plant communities where it did not historically exist or to increase beyond its historic composition within the plant community. For the purpose of this interpretation, encroachment potential is defined as the probability of a Utah juniper seed on a site producing a self-sustaining plant.

The intent of this interpretation is to identify areas that are susceptible to encroachment by Utah juniper, not to identify areas where Utah juniper currently does or does not exist. In addition, it is important to recognize the difference between the rate of encroachment and the potential for encroachment. Some soil map unit components may be susceptible to encroachment, but the rate of encroachment may be very slow. This interpretation focuses only on the factors that influence seedling establishment, not on the factors that influence the rate at which they establish (rate of expansion).

The ratings for Utah juniper encroachment potential are based on the following properties:

1. Taxonomic temperature regime 2. Taxonomic moisture regime 3. Mean annual precipitation 4. Drainage class and water table depth during the growing season 5. Depth to root-restricting layers 6. Electrical conductivity and sodium adsorption ratio in the upper 20 inches 7. Presence of blackbrush (Coleogyne ramosissima) in the reference state plant community

Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.00 to 1.00. They indicate gradations between the point at which a feature results in the greatest risk of Utah juniper encroachment (1.00) and the point at which the feature does not contribute to a risk of Utah juniper encroachment (0.00).

The components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. Only the components that have the same rating class as that given for the map unit are listed. The percent composition of each component in a particular map unit is given to help the user better understand the composition of each map unit that is rated.

Components with different ratings may also be present in a map unit. The ratings for all components, regardless of the aggregated rating of the unit, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

CZSS - Salinization due to Coastal Saltwater Encroachment Research shows that physical and chemical characteristics of soils influence the potential for salinization from coastal saltwater encroachment. Saltwater encroachment is the movement of saline groundwater into the soil. In the Carolina coastal plain, the construction of drainage ditches for agriculture and channelization for navigation has increased the connectivity of the interior soils to the coastal waters. These drainage ditches provide a conduit for the saltwater and can increase the local vulnerability. Marine salts move inland as a result of diffusion and wind tides during droughts and during hurricane storm surges (Ury, et al. 2020). The frequency and duration of these events vary, from pulse events associated with sporadic high-intensity coastal storms to long periods of saltwater saturation from rising sea levels migrating inland. When saltwater moves inland, nutrients that were bound to soil particles can be released in the porewater and carried to nearby tributaries with the movement of tides (Tully, K. L. et. al. 2019). The release of P into solution is likely due to Fe reduction and competition with sulfur in the seawater complex (Tully, K. L. et. al. 2019). FeIII normally binds to P, but when it is reduced (FeII) it will preferentially bind to sulfate ions which allows P to be mobile. This allows P to travel through the connected waterways. Impacts of saltwater inundations and intrusions include forest loss, reductions in crop yields, nutrient release from the soil, marsh migration inland, expansion of salt tolerant species, and degraded groundwater ( Climate Hubs, 2020). As saltwater moves inland, understanding salinization of terrestrial soils will increase our knowledge of environmental impacts along the coast such as marsh migration or the loss of soil fertility in croplands.

Evaluation Criteria This interpretation evaluates soil factors that may influence salinization due to coastal saltwater inundation. It does not consider the duration of the saltwater inundation. The relative height above sea level is estimated by the elevation of the soil components and the Major Land Resource Area in which they occur. Currently, the Tidewater Area, Atlantic Coast Flatwoods, and the Southern Coastal Plain are considered vulnerable. In the early stages of saltwater inundation, high freshwater tables in soils tend to attenuate the impact of salts by reducing the movement of saltwater inland. This eventually leads to lesser impacts from saltwater on soils and lower rates of marsh lateral migration (Hussein, 2009). When saltwater eventually inundates an upland soil, the amount of soluble salts retained is determined by water table fluctuations, soil texture, saturated hydraulic conductivity, cation exchange capacity, and extractable cation exchange capacity (Hussein and Rabenhorst, 2001). Sandy soil materials in upland areas subject to saltwater inundation tend to have reduced impacts from salts due to lower cation exchange capacities, lower extractable cation exchange capacities, and higher saturated hydraulic conductivities (Broome, 1988). In agricultural areas, artificial drainage, whether it is tiles or ditches, allows inland movement of salt-affected water.

The following soil properties and characteristics correspond to criteria identified and deemed significant by the Natural Resources Conservation Service: Depth to Water Table Cation Exchange Capacity or Extractable Cation Exchange Capacity Saturated Hydraulic Conductivity Slope Electrical Conductivity Presence of artificial drainage

Soil Potential Rating Classes The rating class definitions refer to the potential of the soil to retain salts after inundation by coastal saltwater.

High Salinization Hazard (rating value of 0.81 to 1.0): These soils have a combination of characteristics and properties that are very likely to retain salts after saltwater encroachment. Soils will have long-term impacts of salinization due to coastal saltwater inundation. Impacts include forest loss, reductions in crop yields, nutrient release from the soil, marsh migration inland, expansion of salt tolerant species, loss of critical tidal marsh habitat, and degraded groundwater ( Climate Hubs, 2020). Terrestrial soils that already contain ocean-derived salts and have a 1:5 electrical conductivity populated in the National Soils Information System (NASIS) are rated high potential.

Moderately High Salinization Hazard (rating value 0.51 to 0.8): These soils have a combination of characteristics and properties that are likely to retain salts after saltwater encroachment. Soils are likely to have long-term impacts of salinization due to coastal saltwater inundation.

Moderate Salinization Hazard (rating value 0.3 to 0.5): These soils have a combination of characteristics and properties that are somewhat likely to retain salts after saltwater encroachment. Soils may have long-term impacts of salinization due to coastal saltwater inundation.

Low Salinization Hazard (rating value of 0.01 to 0.29): These soils have a combination of characteristics and properties that are not likely retain salts after saltwater encroachment. Soils will have little long-term impacts of salinization due to coastal saltwater inundation.

Not Coastal (rating value of 0.0: These soils are not on the Carolina Coastal Plain so these soils do not have a risk of retaining salts.

Not Rated: Soils or miscellaneous areas labeled Not Rated have characteristics and properties that show extreme variability from one location to another. An onsite investigation may be required to determine soil conditions present at the site. Soils that have a subaqueous drainage class or are miscellaneous soil map units are not rated.

The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is provided to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.

References

Anisfeld, S. C., K. R. Cooper, and A. C. Kemp. 2017 Upslope development of a tidal marsh as a function of upland land use. Global Change Biology 23.2:755-766. https://doi.org/10.1111/gcb.13398.

Bhattachan, A., Emanuel, R.E, Ardon, M., Bernhardt, E. S., Anderson, S. M., Stillwagon, M. G., Ury, E. A., BonDor, T. K., Wright, J. P. 2018. Evaluating the effects of land-use change and future climate change on vulnerability of coastal landscapes to saltwater intrusion. Elementa Science of Anthropocene 6: 62.

Broome, S.W., E.D. Seneca, and W.W. Woodhouse, Jr., 1988. Tidal salt marsh restoration. Aquatic Botany 32: 1-22.

Hussein, A.H. and M.C. Rabenhorst. 2001. Tidal Inundation of transgressive coastal areas: Pedogenesis of salinization and alkalinization. Soil Science Society Of America Journal 65:536544.

Hussein, A.H. 2009. Modeling of Sea-Level Rise and Deforestation in Submerging Coastal Ultisols of Chesapeake Bay. Soil Science Society of America Journal 73(1):185196.

Tully, K. L., Weissman, D., Wyner, W. J., Miller, J., Jordan, T. 2018. Soils in transition: saltwater intrusion alters soil chemistry in agricultural fields. Biogeochemistry 142:339-356

Ury, E. A., Yang, X., Wright, J. P., Bernhardt, E. S. 2021. Rapid deforestation of a coastal landscape driven by sea-level rise and extreme events. Ecological Applications 31(5), e02339.

Climate Hubs. Accessed February 2020. https://www.climatehubs.usda.gov/hubs/southeast/topic/saltwater-intrusion-and-salinization-coastal-forests-and-farms

Valley fever, or coccidioidomycosis, is caused by the soil-borne fungi Coccidioides immitis and Coccidioides posadasii, which are endemic to the southwest United States and a few other places in Central and South America. The symptoms of the disease range from none at all to mild cold or flu-like conditions in most people. However, some people experience the disseminated form of the disease, which can kill. The life cycle of fungus consists of saprophytic and parasitic phases. In the saprophytic phase, the fungi live in soil as entangled mycelia and hyphae. The hyphae grow and mature to produce generally rectangular arthrospores. The arthrospores are 1.5 to 4.5 microns in width and 5 to 30 microns in length. These spores move easily in air currents. The parasitic phase occurs in nature under dry, dusty conditions when a host mammal inhales airborne arthrospores. In this phase, the fungi grow as spherules that mature and burst, releasing endospores that can grow into new spherules in the host lungs, inducing Valley fever. The most common habitat for Coccidioides spp. is thought to be the Lower Sonoran Life Zone. This zone corresponds to the climate of south-central Arizona, where the mean July temperature is about 32 degrees C, the mean January temperature is about 10 degrees C, and the annual rainfall is about 23 cm. High temperatures and salinity in the soil surface have the effect of enhancing Coccidioides spp. while inhibiting its competitors. The fungus needs soil that is moist and then dry and hot to grow and reproduce. Soils containing substantial amounts of organic matter, such as animal burrows or human middens, are also favorable for Coccidioides spp. Coccidioides immitis is found primarily in the Central Valley of California (hence the name Valley fever), while Coccidioides posadasii is found in the endemic areas outside of California. This suggests that the fungus has evolved separate xeric and aridic forms. This separation is significant when considering the timing of wetting and drying cycles needed for the fungi to grow.

The soil criteria that are considered in this soil interpretation are those that have the greatest effect on the spatial and temporal aspects of the growth of the fungi. They include the air temperature, soil salinity, rainfall, soil moisture, and soil water-holding capacity.

Each soil criterion is assigned a numerical rating between 0 and 1. For this interpretation, a rating of 1 represents the most suitable soil and site characteristics, and 0 represents unsuitable soil and site characteristics. Each criterion is calculated separately, and the product of the subrule ratings is reported as the overall soil suitability rating.

Rating classes are defined as follows: Highly suitable (numerical rating 1.0 to 0.8): Soils that are very similar to areas known to be highly endemic. Suitable (numeric rating 0.799 to 0.5): Soils that are similar to highly endemic areas, but may have spatial or temporal differences. Moderately suitable (numerical rating of 0.499 to 0.2): Soils that have features that are suited to the growth of the fungi in some places and in some years. Somewhat suitable (numerical rating 0.199 to 0.1) Soils that may have features that can support the growth of the fungi in some places and in some years. Not habitat (numerical rating of 0.099 to 0): Soils that have one or more characteristics that are not suited to the growth of the fungi. Not Rated: Miscellaneous areas.

References

Edwards, P.Q., and C.E. Palmer. 1957. Prevalence of sensitivity to coccidioidin, with special reference to specific and nonspecific reactions to coccidioidin and to histoplasmin. Dis Chest 31(1):35-60.

Egeberg, R.O., A.E. Elconin, and M.C. Egeberg. 1964. Effect of salinity and temperature on Coccidioides immitis and three antagonistic soil saprophytes. Journal of Bacteriology 88(2):473-476.

Fisher, F.S., M.W. Bultman, and D. Pappagianis. 2000. Operational guidelines (version 1.0) for geological fieldwork in areas endemic for coccidioidomycosis (Valley fever). U.S. Geological Survey Open-File Report 00-348.

Fisher, F.S., M.W. Bultman, S.M. Johnson, D. Pappagianis, and E. Zaborsky. 2007. Coccidioides niches and habitat parameters in the southwestern United States: A matter of scale. Annals of the New York Academy of Science 1111:4772.

Kolivras, K.N., P.S. Johnson, A.C. Comrie, and S.R. Yool. 2001. Environmental variability and coccidioiomycosis (Valley fever). Aerobiologia 17:31-42.

Maddy, K.T. 1957. Ecological factors of the geographic distribution of Coccidioides immitis. Journal of the American Veterinary Medical Association 130(11):475-476.

Maddy, K.T. 1958. The geographic distribution of Coccidioides immitis and possible ecological implications. Arizona Medicine 15:178-188.