Bitterroot Valley Area, Montana
The most common soil here is Chereete, on about 6% of the land: a gravelly coarse sandy loam, gritty and crumbly. Perma and Riverrun come next.
About 82% of the land drains well, and 10% stays wet for long stretches; groundwater comes within two feet of the surface under 12% of it.
USDA rates 94% of the land very limited for a standard septic drain field, and 60% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 5% of the land floods occasionally or more, and bedrock lies within 40 inches under 29% of it.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Bitterroot Valley Area, Montana, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Well drained and the dominant hydrologic group is A (high infiltration, low runoff). The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter. 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 Bitterroot Valley Area, Montana. 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 |
|---|---|---|---|---|---|
| Perma-Whitlash families-Rock outcrop complex, breaklands | 12K | Well drained | A | Very limited | Very limited |
| Holter-Whitlash families, complex, dissected mountain slopes | 7K | Well drained | C | Very limited | Very limited |
| Riverrun-Canarway-Fredburr complex, 0 to 2 percent slopes, occassionally flooded | 6K | Moderately well drained | A | Very limited | Very limited |
| Whitlash, rubbly-Rock outcrop-Quast, stony complex, 15 to 50 percent slopes | 6K | Well drained | D | Very limited | Very limited |
| Gash, occasionally flooded-Riverrun, rarely flooded complex, 0 to 2 percent slopes | 5K | Moderately well drained | A | Very limited | Very limited |
| Riverwash-Water-Riverrun, frequently flooded complex, 0 to 2 percent slopes | 5K | Not rated | Not rated | ||
| Wheelbarrow-Pianohill-Rock outcrop, 15 to 45 percent slopes | 4K | Well drained | C | Very limited | Very limited |
| Macmeal-Kadygulch-Tolman families, complex, dissected mountain slopes | 4K | Well drained | B | Very limited | Very limited |
| Riverrun complex, 0 to 2 percent slopes, rarely flooded | 4K | Moderately well drained | A | Very limited | Very limited |
| Perma, extremely stony-Whitash, rubbly complex, 15 to 45 percent slopes | 4K | Well drained | B | Very limited | Very limited |
| Farnuf-Bitterroot-Wimper complex, 15 to 40 percent slopes | 4K | Well drained | B | Very limited | Very limited |
| Holter-Tolman families, complex, dissected mountain slopes | 4K | Well drained | C | Very limited | Very limited |
| Haccke-Quast-Wemple complex, 8 to 15 percent slopes | 4K | Well drained | B | Somewhat limited | Very limited |
| Curlew-Riverrun complex, 0 to 2 percent slopes, rarely flooded | 3K | Very poorly drained | B/D | Very limited | Very limited |
| Burnt Fork loam, 0 to 4 percent slopes | 3K | Well drained | B | Not limited | Very limited |
| Riverside cobbly sandy loam, 15 to 35 percent slopes | 3K | Excessively drained | A | Very limited | Very limited |
| Riverrun, rarely flooded-Gash, occasionally flooded-Curlew, rarely flooded complex, 0 to 2 percent slopes | 3K | Moderately well drained | A | Very limited | Very limited |
| Chereete-Riverrun, rarely flooded-Curlew, rarely flooded complex, 0 to 8 percent slopes | 3K | Excessively drained | A | Very limited | Very limited |
| Hamilton silt loam, 0 to 4 percent slopes | 3K | Well drained | B | Not limited | Somewhat limited |
| Burnt Fork-Wimper-Fairway complex, 1 to 35 percent slopes | 3K | Well drained | B | 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.
What This Means
Building & Foundations
About 60% 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 94% 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.