Lolo National Forest Area, Montana
The most common soil here is McCay, on about 15% of the land: a ashy fine sandy loam, gritty and crumbly. Mitten and Tevis come next.
About 92% of the land drains well, and 2% stays wet for long stretches; groundwater comes within two feet of the surface under 3% of it.
USDA rates 95% of the land very limited for a standard septic drain field, and 91% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 1% of the land floods occasionally or more, and bedrock lies within 40 inches under 23% 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 Lolo National Forest 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 B (moderate infiltration). The most common soil order is Inceptisols — young soils with minimal horizon development but more than Entisols. 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 Lolo National Forest 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 |
|---|---|---|---|---|---|
| McCay family, broadly convex ridges, weakly weathered metamorphic bedrock | 108K | Well drained | C | Very limited | Very limited |
| Typic Haplocryands-Rock outcrop complex, cirque headwalls | 89K | Well drained | C | Very limited | Very limited |
| Rock outcrop-Specie, extremely stony-Wilde, extremely stony, families, complex, stream breaklands | 86K | D | Not rated | Not rated | |
| McCay family, moderately steep mountain slopes, weakly weathered metasedimentary rock | 79K | Well drained | B | Very limited | Very limited |
| Divers-Oakes families-Rock outcrop complex, glaciated-valley walls | 69K | Well drained | B | Very limited | Very limited |
| Mitten and Tevis families, steep mountain slopes, very stony | 61K | Well drained | B | Very limited | Very limited |
| McCay, cold-McCay families, complex, broadly convex ridges | 60K | Well drained | B | Very limited | Very limited |
| Mitten and Tevis families, moderately steep mountain slopes | 56K | Well drained | B | Very limited | Very limited |
| McCay, Vaywood and Muddycreek families, cirque basins | 47K | Well drained | B | Very limited | Very limited |
| Mitten family, moderately steep mountain slopes, weakly weathered metasedimentary rock | 47K | Well drained | B | Very limited | Very limited |
| Lostbasin family, extremely stony-Rock outcrop complex, stream breaklands | 42K | Well drained | B | Very limited | Very limited |
| Mitten family, extremely stony-Rock outcrop-Tevis family, extremely stony complex, stream breaklands | 42K | Well drained | B | Very limited | Very limited |
| Typic Haplocryands-Constance family-Rock outcrop complex, steep subalpine mountain slopes | 42K | Well drained | D | Very limited | Very limited |
| Beeskove-Bendahl-Foyslake families, complex, moderately steep mountain slopes | 39K | Well drained | B | Very limited | Very limited |
| Vaywood family, glacial-valley floors, extremely bouldery | 37K | Well drained | B | Very limited | Very limited |
| McCay family, steep mountain slopes | 36K | Well drained | B | Very limited | Very limited |
| Lostbasin-Bergquist families, complex, steep mountain slopes, very stony | 35K | Well drained | B | Very limited | Very limited |
| Mitten-Tevis families, complex, moderately steep mountain slopes | 35K | Well drained | B | Very limited | Very limited |
| Broadmoor family, steep mountain slopes, very stony | 33K | Well drained | B | Very limited | Very limited |
| Mitten family, moderately steep mountain slopes | 31K | 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 91% 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 95% 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.