Linn County Area, Oregon

Survey Area OR639• Oregon

The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate 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 Linn County Area, Oregon. 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
Dayton silt loam	58K	Poorly drained	D	Very limited	Very limited
Honeygrove silty clay loam, 12 to 25 percent slopes	32K	Well drained	C	Very limited	Very limited
Harrington-Klickitat complex, 50 to 75 percent south slopes	31K	Well drained	B	Very limited	Very limited
Woodburn silt loam, 0 to 3 percent slopes	29K	Moderately well drained	C	Very limited	Very limited
Amity silt loam	26K	Somewhat poorly drained	C/D	Very limited	Very limited
Bashaw silty clay	25K	Poorly drained	D	Very limited	Very limited
Harrington-Klickitat complex, 50 to 75 percent north slopes	17K	Well drained	B	Very limited	Very limited
Keel gravelly silt loam, 45 to 75 percent slopes	17K	Well drained	C	Very limited	Very limited
Holcomb silt loam	17K	Somewhat poorly drained	D	Very limited	Very limited
Honeygrove silty clay loam, 25 to 50 percent south slopes	16K	Well drained	C	Very limited	Very limited
Coburg silty clay loam	15K	Moderately well drained	C	Very limited	Very limited
Water	14K			Not rated	Not rated
Newberg fine sandy loam	14K	Well drained	A	Very limited	Very limited
Blachly clay loam, 3 to 30 percent slopes	12K	Well drained	C	Very limited	Very limited
Malabon silty clay loam	12K	Well drained	C	Somewhat limited	Very limited
Keel gravelly silt loam, 25 to 45 percent slopes	11K	Well drained	C	Very limited	Very limited
Nekia silty clay loam, 2 to 12 percent slopes	11K	Well drained	C	Very limited	Very limited
Chehalis silty clay loam	11K	Well drained	B	Very limited	Very limited
Concord silt loam	11K	Poorly drained	C/D	Very limited	Very limited
Kinney-Klickitat complex, 50 to 70 percent south slopes	11K	Well drained	B	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.

Inceptisols

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

Ultisols

Strongly weathered clay soils of the Southeast. Acidic and naturally low in nutrients. Clay subsoil can slow drainage.

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.

Andisols

Volcanic ash soils — light, porous, and fertile. Excellent drainage, but low density can complicate foundations.

What This Means

Building & Foundations

About 93% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, 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. 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.