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Soil datasets — including 25+ soil attribute maps—are available in Overyield via an integration with the US Soil Web Survey.

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Downloading & Exploring Soil Data

Adding Soil Layers to the Map:

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Click “New Layer” in the top toolbar → “Soil Boundaries (US).”
You can either load the soil boundaries for your current view, or load for a farm boundary layer previously added to your map.

Viewing Soil Data:

All soil data is accessible via the righthand Layers menu → “Soil boundaries (US)”

Data includes Series name, acreage associated with each soil type, and other properties that can be viewed by selecting different datasets via the “Soil Attributes” dropdown.
Detailed information can be viewed and exported via the “Open Attribute Data” button.

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Available Datasets

Soil Attribute	Definition
Available Water Capacity (AWC)	The amount of water that a soil can store and make available to plants, calculated as the difference between field capacity and wilting point.
Calcium Carbonate (CaCO₃)	The proportion of calcium carbonate in the soil, which influences pH, nutrient availability, and structure.
Cation Exchange Capacity (CEC)	Soil’s capacity to hold and exchange positively charged nutrients (e.g., Ca²⁺, K⁺, Mg²⁺), typically measured at pH 7.
Clay	The percentage of particles less than 0.002 mm—higher clay content affects water retention and drainage.
Drainage Class	A classification describing how well water moves through the soil (e.g., poorly, somewhat poorly, well, excessively drained).
Electrical Conductivity (EC)	A measure of soil solution salinity, indicating total dissolved salts concentration.
Gypsum	The percentage of gypsum (CaSO₄·2H₂O) in the soil, relevant for drainage and fertility.
Hydric Rating	A designation indicating whether a soil is formed under wet, anaerobic conditions (“hydric”), often used in wetland identification.
Hydrologic Group	USDA soil classification (A–D) reflecting infiltration rates—Group A soils drain quickly, Group D very slowly.
Kₙ Factor (Kₓ or Kₙ)	Soil erodibility index used in erosion modeling (e.g., RUSLE) based on texture, structure, organic matter, and permeability.
Ksat (Saturated Hydraulic Conductivity)	A measure of how fast water moves through saturated soil, typically in inches/hour or cm/day.
Land Capability Class	A USDA classification (I–VIII) describing soil suitability for agriculture, considering limitations like erosion risk or moisture.
Linear Extensibility	Indicates soil shrink–swell potential as moisture changes—important for foundation stability.
Map Unit Type	Identifies whether a soil map unit is a single soil series, miscellaneous area, or a mixture.
Organic Matter	Percentage of soil composed of decomposed plant and animal residues—key for structure and nutrients.
pH	A measure of soil acidity or alkalinity (scale ~4–9), crucial for nutrient availability.
Sand	Percentage of particles between 0.05–2 mm—affects texture, drainage, and aeration.
Sodium Adsorption Ratio (SAR)	The ratio of sodium to calcium plus magnesium in soil water—high values can degrade soil structure.
T Factor	The maximum average annual soil loss (in tons per acre per year) that is considered tolerable without degrading long-term productivity.
Wind Erodibility	Factor measuring soil’s susceptibility to wind erosion, based on texture and aggregation.
K Factor, Whole Soil (All Layers)	An estimate of the soil's erodibility averaged across all soil layers. Used in erosion models like RUSLE.
K Factor, Whole Soil (Surface Layer)	Soil erodibility factor specifically for the surface horizon, where erosion is most active.
pH, 1:1 Water (All Layers)	Average soil pH across all layers using a 1:1 water-to-soil ratio. Indicates overall acidity or alkalinity.
pH, 1:1 Water (Surface Layer)	Soil pH measured in the surface horizon using a 1:1 water-to-soil ratio.
Cation Exchange Capacity: CEC-7 (All Layers)	Soil’s capacity to hold exchangeable cations across all layers, measured at pH 7.0.
Cation Exchange Capacity: CEC-7 (Surface Layer)	CEC for the surface layer only. Critical for nutrient availability in biologically active zones.
Farmland Classification	Indicates whether soil is 'prime', 'statewide important', or 'not prime' farmland, based on NRCS standards.
Ponding Frequency Class	Describes how often water collects on the soil surface: none, rare, occasional, or frequent.
Soil Health: Organic Matter (All Layers)	Percentage of organic matter across all soil layers. Important for water retention and fertility.
Soil Health: Organic Matter (Surface Layer)	Organic matter content in the surface layer. Indicator of soil health and microbial activity.