Sweet Grass County Area, Montana
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 Sweet Grass County Area, Montana.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Hinterland-Rentsac-Cabbart complex, 2 to 15 percent slopes | 34K | Well drained | D | Very limited | Very limited |
| Area not surveyed, access denied | 30K | Not rated | Not rated | ||
| Cabbart-Delpoint, calcareous, loams, 2 to 8 percent slopes | 21K | Well drained | D | Very limited | Very limited |
| Yawdim-Rentsac-Cabbart complex, 2 to 15 percent slopes | 21K | Well drained | D | Very limited | Very limited |
| Ashbon-Winkler-Rock outcrop complex, 35 to 60 percent slopes | 20K | Well drained | D | Very limited | Very limited |
| Cabbart, moist-Delpoint-Rock outcrop complex, 15 to 60 percent slopes | 20K | Well drained | D | Very limited | Very limited |
| Castner-Wayden complex, moist, 15 to 60 percent slopes | 20K | Well drained | D | Very limited | Very limited |
| Cabbart-Delpoint loams, moist, 15 to 35 percent slopes | 16K | Well drained | D | Very limited | Very limited |
| Reedpoint very channery loam, 2 to 15 percent slopes | 16K | Well drained | D | Very limited | Very limited |
| Cabbart-Rock outcrop complex, 15 to 60 percent slopes | 15K | Well drained | D | Very limited | Very limited |
| Tamaneen gravelly clay loam, 2 to 8 percent slopes | 14K | Well drained | C | Not limited | Very limited |
| Fairway-Korchea loams, 0 to 4 percent slopes, rarely flooded, channeled | 14K | Well drained | B | Very limited | Somewhat limited |
| Cabba-Castner-Amherst complex, 2 to 15 percent slopes | 14K | Well drained | D | Very limited | Very limited |
| Yawdim-Rentsac complex, 15 to 60 percent slopes | 14K | Well drained | D | Very limited | Very limited |
| Fairway-Korchea-Albicalis loams, 0 to 4 percent slopes, rarely flooded, channeled | 14K | Somewhat poorly drained | C | Very limited | Very limited |
| Wayden-Castner complex, 15 to 60 percent slopes | 13K | Well drained | D | Very limited | Very limited |
| Tanna-Hinterland clay loams, 2 to 8 percent slopes | 13K | Well drained | D | Somewhat limited | Very limited |
| Tanna-Cabbart complex, 2 to 8 percent slopes | 12K | Well drained | D | Somewhat limited | Very limited |
| Cabba, moist-Rock outcrop complex, 15 to 60 percent slopes | 11K | Well drained | D | Very limited | Very limited |
| Reedpoint very channery loam, 15 to 60 percent slopes | 10K | Well drained | D | Very limited | Very limited |
What This Means
Building & Foundations
About 80% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 87% 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.