Custer County Area, Montana

Survey Area MT017• Montana

The dominant drainage class is Well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Inceptisols — young soils with minimal horizon development but more than Entisols. This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Custer County Area, Montana. Search your address to find the exact soil composition, drainage, and series details at your specific location.

Soil Map Unit	Acres	Drainage	Hydro Group	Dwellings	Septic
Cambeth-Cabbart-Yawdim complex, 15 to 25 percent slopes	256K	Well drained	D	Very limited	Very limited
Cabbart-Rock outcrop-Yawdim complex, warm, 15 to 70 percent slopes	225K	Well drained	D	Very limited	Very limited
Sonnett-Sonnett, thin surface, complex, 2 to 8 percent slopes	103K	Well drained	C	Somewhat limited	Very limited
Cambeth, noncalcareous-Megonot complex, 8 to 15 percent slopes	65K	Well drained	C	Somewhat limited	Very limited
Badland	61K			Not rated	Not rated
Cambeth-Cabbart-Rock outcrop complex, 8 to 45 percent slopes	57K	Well drained	D	Somewhat limited	Very limited
Area not surveyed, access denied	56K			Not rated	Not rated
Yamacall-Havre, occasionally flooded, loams, 0 to 8 percent slopes	52K	Well drained	B	Very limited	Very limited
Cabbart-Rock outcrop-Delpoint complex, 15 to 50 percent slopes	50K	Well drained	D	Very limited	Very limited
Lonna-Cambeth-Cabbart silt loams, 4 to 12 percent slopes	48K	Well drained	B	Somewhat limited	Very limited
Lonna-Cambeth-Cabbart silt loams, 12 to 25 percent slopes	44K	Well drained	C	Very limited	Very limited
Cambert-Cabba-Widen complex, 15 to 25 percent slopes	43K	Well drained	D	Very limited	Very limited
Delpoint-Cabbart-Yawdim complex, 25 to 70 percent slopes	41K	Well drained	D	Very limited	Very limited
Delpoint-Yamacall-Cabbart loams, 8 to 25 percent slopes	38K	Well drained	C	Very limited	Very limited
Lonna-Cambeth silt loams, 2 to 8 percent slopes	38K	Well drained	C	Not limited	Very limited
Cabbart-Havre loams, 0 to 35 percent slopes	34K	Well drained	D	Very limited	Very limited
Tinsley gravelly sandy loam, 8 to 35 percent slopes	31K	Excessively drained	A	Very limited	Very limited
Lamedeer-Cabba-Ringling complex, 25 to 70 percent slopes	31K	Well drained	B	Very limited	Very limited
Cambeth, noncalcareous-Megonot complex, 2 to 8 percent slopes	29K	Well drained	C	Somewhat limited	Very limited
Sonnett-Sonnett, thin surface, complex, 0 to 2 percent slopes	26K	Well drained	C	Somewhat limited	Very limited

Soil Orders in This Area

The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.

Inceptisols

Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.

Entisols

Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.

Alfisols

Moderately weathered forest soils with clay-enriched subsoil. Productive for agriculture, generally good for building and septic.

Mollisols

Fertile grassland soils with thick, dark topsoil. Among the best for agriculture, building, and gardening.

Vertisols

High-clay soils that shrink and swell dramatically. Fertile but challenging for foundations and septic systems.

What This Means

Building & Foundations

About 63% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes. A geotechnical assessment is recommended before building.

Septic Systems

About 91% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.

Gardening & Agriculture

Well-drained soils on sloped terrain — good for most plants but watch for erosion. Terracing, contour planting, and mulching help retain moisture and topsoil. Drip irrigation is more effective than sprinklers on slopes.