USDA Regenerative Agriculture Risk Map
Two Lenses on America's Soil Vulnerability
Not all soils respond to disturbance the same way. This map renders two complementary
soil risk interpretations, both derived from the National Cooperative Soil Survey,
that together reveal where the land beneath America's farms and forests is most at risk.
Each interpretation draws on decades of field observation and laboratory analysis,
aggregated to the map unit level and expressed as a dominant condition across millions
of individually surveyed parcels.
Left panel
Fragile Soil Index
The Fragile Soil Index (FSI) measures a soil's inherent susceptibility to structural
breakdown under physical disturbance: tillage, traffic, compaction, and the removal
of protective cover. It integrates texture, organic matter content, aggregate stability,
clay mineralogy, drainage class, and bulk density into a continuous fuzzy-logic score
from 0 to 1. A high score does not mean the soil is already degraded; it means the
soil has little tolerance for disturbance before long-term productivity is compromised.
Fragile soils require conservation-first management practices, including cover crops,
minimal tillage, and careful traffic management, to preserve function across generations.
Classification Criteria · FSI Score Range
Not Fragile
Score 0.00 – 0.15
Highly stable soils with strong aggregate structure, adequate organic matter, and favorable drainage. These soils absorb disturbance with minimal long-term consequence and support intensive use without structural decline.
Slightly Fragile
Score 0.15 – 0.30
Generally resilient soils with minor susceptibility to compaction or aggregate disruption. Good management practices maintain productivity with few restrictions, but bare soil periods should be minimized.
Moderately Fragile
Score 0.30 – 0.50
Soils showing meaningful sensitivity to tillage and compaction. Structural decline under repeated disturbance is measurable. Reduced-tillage systems, residue retention, and cover crops are strongly recommended to prevent irreversible loss.
Highly Fragile
Score 0.50 – 0.70
Soils prone to rapid structural collapse under conventional management. Regenerative land practices are essential. Any period of bare soil exposure or heavy equipment traffic poses a substantial risk of lasting degradation that is difficult and costly to reverse.
Very Highly Fragile
Score 0.70 – 1.00
The most vulnerable soils in the landscape. Even modest disturbance risks severe, potentially irreversible structural failure. These soils are best maintained in permanent vegetative cover, including native grass, woodland, or perennial systems, with the most conservative stewardship practices applied at every stage.
Right panel
Organic Matter Depletion
The Soil Organic Health Organic Matter Depletion interpretation quantifies how
readily a soil will lose its organic matter pool when subjected to tillage, residue
removal, or a change in land use. Organic matter is the engine of soil fertility:
it feeds microbial communities, binds aggregates, retains water, and sequesters
atmospheric carbon. Its loss is largely invisible at the surface yet profoundly
consequential over time. This interpretation weighs clay content and mineralogy
(which anchor organic carbon against decomposition), mean annual temperature
(which governs microbial respiration rates), and precipitation seasonality
(which drives both production and breakdown). Soils that score high are those
where biology and chemistry conspire to accelerate loss under any management that
reduces inputs or exposes the soil surface.
Classification Criteria · Depletion Risk
Low Depletion
Highly stable organic matter pool
High clay content or 2:1 clay mineralogy (smectite) strongly binds organic carbon. Cool climates or high precipitation suppresses decomposition rates. Organic matter is stable or likely to increase under most management regimes.
Moderately Low Depletion
Minor risk under typical management
Favorable conditions for organic matter retention with some sensitivity to management intensity. Maintaining residue cover and limiting fallow periods will hold organic matter at productive levels with moderate effort.
Moderate Depletion
Measurable loss under tillage
Tillage and residue removal produce measurable organic matter reductions over a 5–10 year horizon. Cover crops, manure additions, and reduced-till systems are beneficial and often necessary to maintain soil quality indicators within productive ranges.
Moderately High Depletion
Significant risk; active management required
Sandy textures, warm temperatures, or kaolinitic mineralogy combine to accelerate organic matter turnover. Organic matter losses can be rapid and are difficult to replace. Continuous-cover systems and high organic matter inputs are necessary to stabilize the pool.
High Depletion
Rapid, severe loss under disturbance
The most vulnerable soils for organic matter retention. Coarse texture, high temperatures, and low clay activity create conditions where organic carbon oxidizes rapidly with any reduction in plant inputs. These soils require continuous organic matter additions, permanent cover, and minimal soil disturbance to maintain functional capacity.
Data source: USDA Natural Resources Conservation Service,
National Cooperative Soil Survey (NCSS). Interpretations computed via the
Soil Data Access (SDA) tabular endpoint using dominant condition aggregation
across all major soil components per map unit. Values reflect the most recent
official SSURGO soil survey data for each survey area.
Geographic coverage: All 50 states, DC, and US territories
where SSURGO spatial data has been published.
County values are area-weighted averages derived from spatial intersection
of map unit polygon geometry with Census county boundaries.