Coronado National Forest, Arizona, Parts of Cochise, Graham, Pima and Pinal Counties
The dominant drainage class is Well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). 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 Coronado National Forest, Arizona, Parts of Cochise, Graham, Pima and Pinal Counties.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Lithic Argiustolls, Typic Haplustolls, and Aridic Calciustolls; warm mesic ustic mountains | 639K | Well drained | D | Very limited | Very limited |
| Calcic Petrocalcids, Typic Haplocalcids, and Lithic Ustic Torriorthents; cool thermic aridic fan remnants and hills | 178K | Well drained | D | Very limited | Very limited |
| Lithic Argiustolls, Typic Haplustolls, and Vitrandic Haplustolls; cool mesic ustic mountains | 111K | Well drained | D | Very limited | Very limited |
| Ustic Haplocalcids, Ustic Haplocambids, rarely flooded, and Typic Torripsamments, rarely flooded; cool thermic aridic alluvial fans | 75K | Well drained | B | Very limited | Very limited |
| Ustic Haplargids and Typic Torriorthents; cool thermic aridic fan piedmonts | 45K | Well drained | C | Very limited | Very limited |
| Lithic Argiustolls, Cumulic Haplustolls, rarely flooded, and Typic Ustorthents; warm mesic ustic mountains | 17K | Well drained | C | Very limited | Very limited |
| Ustic Haplargids, Ustic Torrifluvents, rarely flooded, and Ustic Haplocambids; warm thermic aridic hills and fans | 15K | Well drained | A | Very limited | Very limited |
| Typic Haplargids, Ustic Haplocambids, and Ustic Calciargids; warm thermic basins and fan remnants | 182 | Well drained | C | Somewhat limited | Very limited |
What This Means
Building & Foundations
About 99% 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 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.