Harper County, Oklahoma

Survey Area OK059• Oklahoma

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 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 Harper County, Oklahoma. 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
Quinlan-Rock outcrop-Yomont complex, 0 to 45 percent slopes	53K	Well drained	D	Very limited	Very limited
Selman silt loam, 1 to 3 percent slopes	49K	Well drained	B	Not limited	Somewhat limited
Quinlan-Woodward-Deepwood complex, 5 to 12 percent slopes	48K	Well drained	D	Very limited	Very limited
Westola-Quinlan-Hardeman complex, 0 to 12 percent slopes	42K	Well drained	B	Very limited	Very limited
Woodward-Quinlan complex, 3 to 5 percent slopes	35K	Well drained	C	Somewhat limited	Very limited
Tivoli fine sand, 5 to 12 percent slopes	21K	Excessively drained	A	Somewhat limited	Very limited
Eda sand, 1 to 12 percent slopes	21K	Somewhat excessively drained	A	Not limited	Very limited
St. Paul silt loam, 1 to 3 percent slopes	19K	Well drained	C	Somewhat limited	Very limited
Selman silt loam, 3 to 5 percent slopes	18K	Well drained	B	Not limited	Somewhat limited
Woodward-Quinlan complex, 1 to 3 percent slopes	17K	Well drained	C	Somewhat limited	Very limited
Cottonwood-Rock outcrop-Vinson complex, 3 to 12 percent slopes	14K	Well drained	D	Very limited	Very limited
Rock outcrop-Cottonwood complex, 12 to 80 percent slopes	13K		D	Very limited	Very limited
St. Paul silt loam, 0 to 1 percent slopes	13K	Well drained	C	Somewhat limited	Very limited
Hardeman fine sandy loam, 1 to 3 percent slopes, cool	12K	Well drained	A	Not limited	Very limited
Lincoln sand, 0 to 1 percent slopes, occasionally flooded	12K	Somewhat excessively drained	A	Very limited	Very limited
Jester loamy fine sand, 1 to 5 percent slopes	12K	Excessively drained	A	Not limited	Very limited
Tivoli fine sand, 12 to 45 percent slopes	10K	Excessively drained	A	Very limited	Very limited
Alopark-Mocane complex, 1 to 3 percent slopes	9K	Well drained	A	Not limited	Not limited
Grandfield fine sandy loam, 1 to 3 percent slopes	9K	Well drained	B	Not limited	Very limited
Quinlan-Woodward complex, 5 to 8 percent slopes	9K	Well drained	D	Very 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.

Inceptisols

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

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.

What This Means

Building & Foundations

About 46% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.

Septic Systems

About 82% 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.