Alsea Area, Oregon

Survey Area OR601• Oregon

The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Alsea 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
Bohannon gravelly loam, dissected, 50 to 90 percent slopes	40K	Well drained	B	Very limited	Very limited
Bohannon-Slickrock gravelly loams, dissected, 37 to 50 percent slopes	19K	Well drained	B	Very limited	Very limited
Slickrock gravelly loam, 25 to 37 percent slopes	13K	Well drained	B	Very limited	Very limited
Bohannon gravelly loam, dissected, 37 to 50 percent slopes	11K	Well drained	B	Very limited	Very limited
Bohannon-Slickrock gravelly loams, 35 to 50 percent slopes	7K	Well drained	B	Very limited	Very limited
Slickrock gravelly loam, dissected, 25 to 37 percent slopes	6K	Well drained	B	Very limited	Very limited
Bohannon gravelly loam, 50 to 75 percent slopes	6K	Well drained	B	Very limited	Very limited
Bohannon gravelly loam, 35 to 50 percent slopes	6K	Well drained	B	Very limited	Very limited
Preacher clay loam, ridge, 0 to 25 percent slopes	5K	Well drained	B	Somewhat limited	Very limited
Slickrock gravelly loam, dissected, 37 to 50 percent slopes	4K	Well drained	B	Very limited	Very limited
Nehalem silt loam	3K	Well drained	B	Very limited	Very limited
Slickrock gravelly loam, 37 to 50 percent slopes	3K	Well drained	B	Very limited	Very limited
Colluvial and Alluvial land	3K	Well drained	B	Somewhat limited	Somewhat limited
Bohannon-Slickrock gravelly loams, dissected, 25 to 37 percent slopes	3K	Well drained	B	Very limited	Very limited
Bohannon gravelly loam, ridge, 25 to 37 percent slopes	3K	Well drained	B	Very limited	Very limited
Bohannon loam, ridge, 5 to 25 percent slopes	3K	Well drained	B	Very limited	Very limited
Water	3K			Not rated	Not rated
Bohannon-Slickrock gravelly loams, 25 to 35 percent slopes	2K	Well drained	B	Very limited	Very limited
Bohannon-Slickrock gravelly loams, dissected, 50 to 75 percent slopes	2K	Well drained	B	Very limited	Very limited
Klickitat gravelly clay loam, dissected, 50 to 85 percent slopes	2K	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.

Andisols

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

Mollisols

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

Spodosols

Acidic forest soils with a leached layer. Common under conifers. Often have drainage issues from a compacted subsoil layer.

What This Means

Building & Foundations

About 92% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, 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.