Susanville Area, Parts of Lassen and Plumas Counties, California

Survey Area CA608• California

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 Susanville Area, Parts of Lassen and Plumas Counties, California. 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
Water	125K		D	Not rated	Not rated
Petescreek-Fredonyer association 2 to 30 percent slopes	72K	Well drained	C	Very limited	Very limited
Devada-Petescreek-Fiddler association, 2 to 30 percent slopes	69K	Well drained	D	Very limited	Very limited
Ravendale silty clay, 0 to 2 percent slopes, occasionally flooded	68K	Moderately well drained	C	Very limited	Very limited
Devada-Rock outcrop association, 2 to 50 percent slopes	50K	Well drained	D	Very limited	Very limited
Petescreek-Searles association, 9 to 30 percent slopes	46K	Well drained	C	Very limited	Very limited
Horsecamp-Brubeck association, 2 to 9 percent slopes	31K	Well drained	C	Very limited	Very limited
Eaglelake-Outland-Weste complex, 9 to 30 percent slopes	29K	Well drained	C	Very limited	Very limited
Searles-Devada-Fivesprings association, 2 to 30 percent slopes	27K	Well drained	D	Very limited	Very limited
Longcreek-Devada-Rubble land complex, 9 to 30 percent slopes	27K	Well drained	D	Very limited	Very limited
Anawalt-Ninemile association, 5 to 15 percent slopes	26K	Well drained	D	Very limited	Very limited
Searles-Orhood-Devada association, 5 to 30 percent slopes	25K	Well drained	D	Very limited	Very limited
Devada-Brubeck association, 2 to 9 percent slopes	21K	Well drained	D	Very limited	Very limited
Buckbay-Orhood-Devada association, 2 to 30 percent slopes	21K	Well drained	D	Very limited	Very limited
Searles-Glean association, 5 to 30 percent slopes	19K	Well drained	C	Very limited	Very limited
Searles-Glean association, 30 to 50 percent slopes	19K	Well drained	C	Very limited	Very limited
Said-Ninemile association, 2 to 30 percent slopes	18K	Well drained	C	Very limited	Very limited
Fiddler-Orhood-Petescreek association, 5 to 30 percent slopes	18K	Well drained	D	Very limited	Very limited
Glenbrook-Graufels-Rock outcrop complex, 30 to 60 percent slopes	18K	Somewhat excessively drained	D	Very limited	Very limited
Rubble land-Fiddler association, 15 to 50 percent slopes	17K	Excessively drained		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.

Aridisols

Dry-climate soils with low organic matter. Often have caliche layers that make excavation difficult. Low shrink-swell is good for foundations.

Alfisols

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

Andisols

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

Inceptisols

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

Vertisols

High-clay soils that shrink and swell dramatically. Fertile but challenging for foundations and septic systems.

What This Means

Building & Foundations

About 83% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, flood-prone areas. A geotechnical assessment is recommended before building.

Septic Systems

About 83% 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.