Coconino County Area, Arizona, Central Part

Survey Area AZ631• 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 Aridisols — dry-climate soils with limited organic matter and often calcium carbonate accumulation. 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 Coconino County Area, Arizona, 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
Winona-Boysag gravelly loams, 0 to 8 percent slopes	309K	Well drained	D	Very limited	Very limited
Winona stony loam, 0 to 8 percent slopes	132K	Well drained	D	Very limited	Very limited
Winona gravelly loam, 0 to 8 percent slopes	125K	Well drained	D	Very limited	Very limited
Thunderbird-Springerville association, strongly sloping	106K	Well drained	D	Very limited	Very limited
Epikom complex, 0 to 15 percent slopes	105K	Well drained	D	Very limited	Very limited
Meriwhitica-Wayneco-Tassi complex, warm, 1 to 11 percent slopes	85K	Well drained	D	Very limited	Very limited
Disterheff very gravelly sandy clay loam, 1 to 15 percent slopes	76K	Well drained	C	Very limited	Very limited
Winona-Rock outcrop complex, 15 to 30 percent slopes	71K	Well drained	D	Very limited	Very limited
Deama-Rock outcrop complex, 8 to 30 percent slopes	61K	Well drained	D	Very limited	Very limited
Deama gravelly loam, 2 to 15 percent slopes	56K	Well drained	D	Very limited	Very limited
Rune-Disterheff association, gently sloping	46K	Well drained	C	Very limited	Very limited
Ashfork gravelly clay loam, 1 to 15 percent slopes	45K	Well drained	D	Very limited	Very limited
Thunderbird-Rock outcrop complex, 30 to 60 percent slopes	41K	Well drained	D	Very limited	Very limited
Winona-Tusayan association, gently sloping	39K	Well drained	D	Very limited	Very limited
Purgatory gravelly fine sandy loam, 0 to 8 percent slopes	36K	Well drained	C	Very limited	Very limited
Deama stony loam, 1 to 15 percent slopes	36K	Well drained	D	Very limited	Very limited
Daze-Deama association, moderately steep	36K	Well drained	D	Very limited	Very limited
Poley-Tusayan association, gently sloping	34K	Well drained	C	Not limited	Somewhat limited
Poley gravelly loam, 0 to 8 percent slopes	34K	Well drained	C	Not limited	Somewhat limited
Rune silty clay loam, 0 to 8 percent slopes	32K	Well drained	C	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.

Aridisols

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

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.

Entisols

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

Vertisols

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

What This Means

Building & Foundations

About 95% 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 95% 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.