Beaverhead National Forest Area, Montana
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 Beaverhead National Forest Area, Montana.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Waldbillig-Bata-Upsata families, complex, glacial moraines | 59K | Well drained | B | Very limited | Very limited |
| Como-Petty families, complex, moderately steep mountain slopes | 49K | Somewhat excessively drained | A | Very limited | Very limited |
| Garlet-Worock-Como families, complex, moderately steep mountain slopes | 40K | Well drained | B | Very limited | Very limited |
| Como-Comad-Garlet families, complex, moderately steep mountain slopes | 38K | Somewhat excessively drained | A | Very limited | Very limited |
| Upsata-Bata-Petty families, complex, glacial moraines | 32K | Excessively drained | B | Very limited | Very limited |
| Garlet-Worock-Como families, complex, gentle mountain slopes | 32K | Well drained | B | Somewhat limited | Very limited |
| Petty-Garlet families, complex, valley trough walls | 31K | Somewhat excessively drained | B | Very limited | Very limited |
| Tiban-Raynesford-Woodhurst families, complex, gentle mountain slopes | 28K | Well drained | C | Somewhat limited | Very limited |
| Littlesalmon-Como families-Rock outcrop complex, valley trough walls | 27K | Somewhat excessively drained | A | Very limited | Very limited |
| Garlet-Holloway-Bata families, complex, moderately steep mountain slopes | 26K | Well drained | B | Very limited | Very limited |
| Como-Leighcan families-Rock outcrop complex, cirque basins | 25K | Somewhat excessively drained | A | Somewhat limited | Very limited |
| Adel-Garlet-Yellowmule families, complex, landslide deposits | 25K | Well drained | B | Very limited | Very limited |
| Waldbillig-Bata-Lowder, frequently flooded families, complex, cirque basins | 23K | Well drained | B | Somewhat limited | Very limited |
| Como-Elkner-Lowder, frequently flooded families, complex, glacial moraines | 22K | Somewhat excessively drained | A | Very limited | Very limited |
| Garlet-Como families-Rock outcrop complex, steep mountain slopes | 21K | Well drained | B | Very limited | Very limited |
| Elkner-Como families-Rock outcrop complex, recessional moraines | 20K | Somewhat excessively drained | A | Very limited | Very limited |
| Rock outcrop-Roman family-Rubble land association, cirque headwalls and scoured basins | 20K | D | Not rated | Not rated | |
| Upsata-Bata-Lowder, frequently flooded families, complex, cirque basins | 20K | Excessively drained | B | Somewhat limited | Very limited |
| Rubble land-Rock outcrop-Crawfish family, complex, cirque headwalls | 18K | D | Not rated | Not rated | |
| Bata-Petty-Worock families, complex, alluvial fans | 18K | Well drained | C | Very limited | Very limited |
What This Means
Building & Foundations
About 70% 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 93% 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.