Challis National Forest, Western Part, Idaho
The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Challis National Forest, Western Part, Idaho.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Typic Haplocryepts, Typic Haplocryolls, very stony surface, and Typic Haplocryepts, high effective precipitation soils, 30 to 70 percent slopes | 237K | Well drained | B | Very limited | Very limited |
| Xeric Haplocryepts-Typic Haplocryepts-Typic Haplocryolls families complex, 25 to 70 percent slopes | 100K | Well drained | B | Very limited | Very limited |
| Pachic Argicryolls, Mollic Haplocryalfs, and Typic Haplocryolls soils, 30 to 65 percent slopes | 79K | Well drained | B | Very limited | Very limited |
| Typic Argixerolls and Pachic Haploxerolls soils, 30 to 70 percent slopes | 77K | Well drained | C | Very limited | Very limited |
| Xeric Haplocryolls and Pachic Argicryolls soils, 30 to 65 percent slopes | 73K | Well drained | B | Very limited | Very limited |
| Lithic Haplocryepts family, very stony surface-Typic Haplocryepts family complex, 25 to 65 percent slopes | 72K | Well drained | D | Very limited | Very limited |
| Pachic Haplocryolls, Pachic Argicryolls, and Lithic Haplocryolls, very bouldery surface soils, 30 to 70 percent slopes | 65K | Well drained | B | Very limited | Very limited |
| Typic Haplocryepts family, extremely stony surface-Typic Cryorthents family, very bouldery surface-Typic Haplocryalfs family complex, 25 to 70 percent slopes | 63K | Somewhat excessively drained | A | Very limited | Very limited |
| Xeric Haplocryepts-Typic Haplocryepts families complex, 15 to 35 percent slopes | 54K | Somewhat excessively drained | A | Very limited | Very limited |
| Xeric Argicryolls-Typic Haplocryalfs-Xeric Haplocryepts families complex, 35 to 70 percent slopes | 50K | Well drained | C | Very limited | Very limited |
| Xeric Haplocryepts-Typic Haplocryepts families complex, 20 to 65 percent slopes | 43K | Well drained | B | Very limited | Very limited |
| Humic Vitricryands, Humic Vitricryands, steep, and Vitrandic Humicryepts soils, 10 to 55 percent slopes | 41K | Well drained | B | Very limited | Very limited |
| Pachic Argixerolls family-Xeric Argicryolls family, extremely bouldery surface-Pachic Argicryolls family complex, 12 to 65 percent slopes | 36K | Well drained | C | Very limited | Very limited |
| Pachic Argicryolls-Xeric Argicryolls-Typic Haplocryalfs families complex, 15 to 65 percent slopes | 36K | Well drained | C | Very limited | Very limited |
| Xeric Haplocryalfs-Pachic Argicryolls-Typic Argixerolls families complex, 6 to 60 percent slopes | 32K | Well drained | C | Very limited | Very limited |
| Xeric Humicryepts-Pachic Haploxerolls-Typic Haplocryepts families complex, 20 to 65 percent slopes | 31K | Well drained | A | Very limited | Very limited |
| Typic Haplocryalfs-Typic Haplocryepts families complex, 5 to 65 percent slopes, very stony surface | 27K | Well drained | C | Very limited | Very limited |
| Pachic Argicryolls-Typic Haplocryalfs families complex, 12 to 30 percent slopes | 26K | Well drained | C | Very limited | Very limited |
| Xeric Haplocryolls-Typic Haploxerolls-Lithic Haplocryolls families complex, 35 to 65 percent slopes | 23K | Somewhat excessively drained | C | Very limited | Very limited |
| Typic Haplocryepts-Xeric Haplocryepts families complex, 35 to 70 percent slopes | 21K | Well drained | B | Very limited | Very limited |
What This Means
Building & Foundations
About 100% 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.