Marion County, Iowa

Survey Area IA125• Iowa

The dominant drainage class is Moderately well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter. 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 Marion County, Iowa. 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
Munterville silt loam, 14 to 18 percent slopes, moderately eroded	21K	Moderately well drained	D	Very limited	Very limited
Water, lakes and reservoirs	18K			Not rated	Not rated
Clinton silt loam, 9 to 14 percent slopes, eroded	15K	Moderately well drained	C	Somewhat limited	Very limited
Ladoga silt loam, 5 to 9 percent slopes, eroded	15K	Moderately well drained	C	Somewhat limited	Very limited
Sharpsburg silty clay loam, 5 to 9 percent slopes, eroded	13K	Moderately well drained	C	Somewhat limited	Very limited
Clinton silt loam, 5 to 9 percent slopes, eroded	13K	Moderately well drained	C	Somewhat limited	Very limited
Sharpsburg silty clay loam, 2 to 5 percent slopes	13K	Moderately well drained	C	Somewhat limited	Very limited
Grundy silty clay loam, 2 to 5 percent slopes	11K	Somewhat poorly drained	C/D	Very limited	Very limited
Clearfield-Arispe silty clay loams, 5 to 9 percent slopes, moderately eroded	10K	Poorly drained	C/D	Very limited	Very limited
Ladoga silt loam, 9 to 14 percent slopes, eroded	10K	Moderately well drained	C	Somewhat limited	Very limited
Pershing silt loam, 5 to 9 percent slopes, moderately eroded	9K	Somewhat poorly drained	D	Very limited	Very limited
Lawson-Quiver-Nodaway complex, 0 to 2 percent slopes, occasionally flooded	9K	Poorly drained	C/D	Very limited	Very limited
Lindley loam, 14 to 18 percent slopes	7K	Well drained	C	Very limited	Very limited
Colo, occasionally flooded-Ely silty clay loams, dissected till plain, 2 to 5 percent slopes	6K	Poorly drained	C/D	Very limited	Very limited
Otley silty clay loam, 5 to 9 percent slopes, eroded	6K	Moderately well drained	C	Very limited	Very limited
Lamoni silty clay loam, 9 to 14 percent slopes, moderately eroded	6K	Somewhat poorly drained	D	Very limited	Very limited
Munterville silt loam, 9 to 14 percent slopes, moderately eroded	6K	Moderately well drained	D	Very limited	Very limited
Munterville silt loam, 18 to 25 percent slopes, moderately eroded	6K	Moderately well drained	D	Very limited	Very limited
Weller silt loam, 5 to 9 percent slopes, moderately eroded	5K	Moderately well drained	D	Very limited	Very limited
Ladoga silt loam, 2 to 5 percent slopes	5K	Moderately 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.

Mollisols

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

Alfisols

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

Entisols

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

Inceptisols

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

What This Means

Building & Foundations

About 49% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.

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.