Siskiyou County, California, Central Part

Survey Area CA602• California

The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate 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 Siskiyou County, California, Central Part. 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
Duzel-Jilson-Facey complex, 15 to 50 percent slopes	103K	Well drained	C	Very limited	Very limited
Marpa-Kinkel-Boomer, cool complex, 15 to 50 percent slopes	80K	Well drained	C	Very limited	Very limited
Kindig-Neuns gravelly loams, 50 to 80 percent slopes complex	47K	Well drained	B	Very limited	Very limited
Lassen-Kuck complex, stony, 2 to 50 percent slopes	46K	Well drained	D	Very limited	Very limited
Lassen-Rock outcrop-Kuck complex, 2 to 50 percent slopes	36K	Well drained	D	Very limited	Very limited
Jilson-Duzel gravelly loams, 5 to 50 percent slopes complex	28K	Well drained	D	Very limited	Very limited
Lithic Haploxerolls-Rock outcrop complex, 0 to 65 percent slopes*	24K	Excessively drained	D	Very limited	Very limited
Mary-Rock outcrop complex, 2 to 50 percent slopes	22K	Well drained	C	Very limited	Very limited
Lithic Xerorthents-Rock outcrop complex, 0 to 65 percent slopes*	21K	Excessively drained	D	Very limited	Very limited
Rock outcrop	17K	Excessively drained	D	Very limited	Very limited
Gazelle silt loam	16K	Very poorly drained	B/D	Very limited	Very limited
Mary stony loam, 2 to 50 percent slopes	16K	Well drained	C	Very limited	Very limited
Salisbury cobbly loam, 0 to 9 percent slopes	14K	Well drained	D	Very limited	Very limited
Settlemeyer loam, 0 to 2 percent slopes	13K	Poorly drained	C/D	Very limited	Very limited
Chaix-Chawanakee gravelly coarse sandy loams, 50 to 70 percent slopes complex	12K	Well drained	B	Very limited	Very limited
Pinehurst stony loam, 2 to 15 percent slopes	10K	Well drained	C	Somewhat limited	Very limited
Sheld-Iller stony sandy loams, 9 to 30 percent slopes complex	10K	Well drained	B	Very limited	Very limited
Plutos-Rock outcrop complex, 0 to 30 percent slopes	9K	Somewhat excessively drained	A	Very limited	Very limited
Pinehurst stony loam, 15 to 30 percent slopes	9K	Well drained	C	Very limited	Very limited
Avis-Oosen complex, 5 to 30 percent slopes	9K	Somewhat excessively drained	A	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.

Vertisols

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

Entisols

Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.

What This Means

Building & Foundations

About 98% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.

Septic Systems

About 100% 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.