Humboldt County, Iowa

Survey Area IA091• Iowa

The dominant drainage class is Poorly drained and the dominant hydrologic group is C/D (varies with drainage). 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 Humboldt 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
Canisteo clay loam, 0 to 2 percent slopes	86K	Poorly drained	C/D	Very limited	Very limited
Clarion loam, 2 to 6 percent slopes	47K	Moderately well drained	C	Somewhat limited	Very limited
Webster clay loam, 0 to 2 percent slopes	33K	Poorly drained	C/D	Very limited	Very limited
Nicollet clay loam, 1 to 3 percent slopes	30K	Somewhat poorly drained	C/D	Very limited	Very limited
Okoboji silty clay loam, 0 to 1 percent slopes	8K	Very poorly drained	C/D	Very limited	Very limited
Garmore clay loam, 0 to 2 percent slopes	8K	Moderately well drained	C	Somewhat limited	Very limited
Harps clay loam, 0 to 2 percent slopes	7K	Poorly drained	C/D	Very limited	Very limited
Wacousta silty clay loam, depressional, 0 to 1 percent slopes	6K	Very poorly drained	C/D	Very limited	Very limited
Clarion loam, 6 to 10 percent slopes, moderately eroded	5K	Well drained	B	Somewhat limited	Somewhat limited
Spillville-Coland complex, channeled, 0 to 2 percent slopes, frequently flooded	5K	Somewhat poorly drained	B/D	Very limited	Very limited
Harps-Okoboji complex, 0 to 2 percent slopes	5K	Poorly drained	C/D	Very limited	Very limited
Lester loam, 2 to 6 percent slopes	4K	Well drained	C	Somewhat limited	Very limited
Clarion-Storden complex, 6 to 10 percent slopes, moderately eroded	3K	Well drained	B	Somewhat limited	Somewhat limited
Calcousta silty clay loam, 0 to 1 percent slopes	2K	Very poorly drained	C/D	Very limited	Very limited
Ridgeport sandy loam, 0 to 2 percent slopes	2K	Somewhat excessively drained	A	Not limited	Very limited
Biscay clay loam, 0 to 2 percent slopes	1K	Poorly drained	C/D	Very limited	Very limited
Okoboji mucky silty clay loam, depressional, 0 to 1 percent slopes	1K	Very poorly drained	C/D	Very limited	Very limited
Wadena loam, 0 to 2 percent slopes	1K	Well drained	B	Not limited	Very limited
Wacousta mucky silty clay loam, depressional, 0 to 1 percent slopes	1K	Very poorly drained	C/D	Very limited	Very limited
Rolfe silt loam, 0 to 1 percent slopes	1K	Very poorly drained	C/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.

Alfisols

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

Inceptisols

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

What This Means

Building & Foundations

About 72% of soils are rated "very limited" for dwellings with basements. Specific challenges include poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.

Septic Systems

About 96% of soils are rated "very limited" for septic absorption fields. Poorly drained soils can't absorb septic effluent effectively. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.

Gardening & Agriculture

Many soils hold water for extended periods. Raised beds are highly recommended to improve drainage for vegetables. Well-adapted native plants and water-loving species will do best in natural conditions.