San Carlos Indian Reservation, Arizona, Parts of Gila and Graham Counties

Survey Area AZ675• Arizona

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 San Carlos Indian Reservation, Arizona, Parts of Gila and Graham Counties. 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
Pachic Argiustolls-Dedal-Rock outcrop complex, 8 to 35 percent slopes	125K	Well drained	C	Very limited	Very limited
Kuykendall-Beaumain-Rock outcrop complex, 5 to 45 percent slopes	115K	Well drained	D	Very limited	Very limited
Beaumain-Rock outcrop-Cherrycow complex, 5 to 60 percent slopes MLRA 38	78K	Well drained	D	Very limited	Very limited
Terrarossa-Cloverdale-Blacktail complex, 1 to 35 percent slopes	62K	Well drained	C	Somewhat limited	Very limited
Torriorthents, 3 to 60 percent slopes	58K	Well drained	C	Very limited	Very limited
Thimble-Rock outcrop complex, 10 to 50 percent slopes	53K	Well drained	D	Very limited	Very limited
Eskiminzin and Sontag soils, and rock outcrop, 0 to 5 percent slopes	52K	Well drained	D	Very limited	Very limited
Brolliar-Dedal complex, 0 to 8 percent slopes	48K	Well drained	D	Very limited	Very limited
Tombstone-Eloma-Pedregosa complex, 5 to 65 percent slopes mlra 38	46K	Well drained	A	Very limited	Very limited
Bigtoe-Ryallen-Tombstone complex, 3 to 30 percent slopes	44K	Well drained	D	Somewhat limited	Very limited
Eloma very gravelly sandy clay loam, 3 to 65 percent slopes mlra 38	43K	Well drained	C	Very limited	Very limited
Bylas-Rock outcrop-Frye complex, 0 to 20 percent slopes	41K	Well drained	D	Very limited	Very limited
Gavilan family-Sponiker complex, 1 to 25 percent slopes	38K	Well drained	C	Very limited	Very limited
Anezul-Dedal-Rock outcrop complex, 2 to 20 percent slopes	36K	Well drained	D	Very limited	Very limited
Topawa-Rillino-Eba complex, 3 to 50 percent slopes	35K	Well drained	C	Very limited	Very limited
Topawa very gravelly sandy loam, 3 to 15 percent slopes	34K	Well drained	C	Somewhat limited	Very limited
Rock outcrop and Ustorthents and haplustolls soils, 40 to 80 percent slopes	34K	Well drained	D	Very limited	Very limited
Eskiminzin-Rock outcrop complex, 35 to 65 percent slopes	33K	Well drained	D	Very limited	Very limited
Turquoise-Rock outcrop-Nugget complex, 20 to 70 percent slopes	33K	Well drained	D	Very limited	Very limited
Argic Petrocalcids-Rock outcrop-Torriorthents complex, 2 to 60 percent slopes	32K	Well drained	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.

Aridisols

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

Entisols

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

Alfisols

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

What This Means

Building & Foundations

About 86% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes. 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.