Montana Soil Surveys
Montana has 70 USDA soil survey areas covering a wide range of landscapes and soil conditions. The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter, making up roughly 47% of surveyed soils. Inceptisols — young soils with minimal horizon development but more than Entisols account for another 23%.
In terms of drainage, 91% of Montana soils are classified as well drained. Drainage class affects everything from septic system design to basement feasibility to garden planning. Use the survey area pages below to see drainage details for specific counties, or look up any address for an exact soil profile.
Soil Types
Mollisols
47% of surveyed soils
Fertile grassland soils with thick, dark topsoil. Among the best for agriculture, building, and gardening.
Inceptisols
23% of surveyed soils
Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.
Entisols
12% of surveyed soils
Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.
Alfisols
10% of surveyed soils
Moderately weathered forest soils with clay-enriched subsoil. Productive for agriculture, generally good for building and septic.
Aridisols
2% of surveyed soils
Dry-climate soils with low organic matter. Often have caliche layers that make excavation difficult. Low shrink-swell is good for foundations.
Vertisols
1% of surveyed soils
High-clay soils that shrink and swell dramatically. Fertile but challenging for foundations and septic systems.
Survey Areas
Absaroka-Beartooth Wilderness Area, Montana, Eastern PartAbsaroka-Beartooth Wilderness Area, Montana, Western PartBeaverhead National Forest Area, MontanaBig Hole Area - Part of Beaverhead County, MontanaBig Horn County Area, MontanaBitterroot National Forest Area, MontanaBitterroot Valley Area, MontanaBlaine County and Part of Phillips County Area, MontanaBob Marshall, Scapegoat, Great Bear, and Mission Mtn. Wilderness Area, MontanaBroadwater County Area, MontanaCarbon County Area, MontanaCarter County, MontanaCascade County Area, MontanaChoteau-Conrad Area; Parts of Teton and Pondera Counties, MontanaChouteau County Area, MontanaCuster County Area, MontanaDawson County, MontanaDeer Lodge County Area, MontanaDeer Lodge National Forest Area, MontanaDillon Area - Part of Beaverhead County, MontanaFallon County, MontanaFergus County, MontanaFlathead County Area and Part of Lincoln County, MontanaFlathead Indian Reservation Wilderness Area, MontanaFlathead National Forest Area, MontanaGallatin County Area, MontanaGallatin National Forest Area, MontanaGarfield County, MontanaGlacier County Area and Part of Pondera County, MontanaGlacier National Park Area - Parts of Glacier and Flathead Counties, MontanaGolden Valley County Area, MontanaGranite County Area, MontanaHelena National Forest Area, MontanaHill County, MontanaHorse Prairie-South Valley Area - Part of Beaverhead County, MontanaJefferson County Area and Part of Silver Bow County, MontanaJudith Basin Area, MontanaKootenai National Forest Area, Montana-IdahoLake County Area, MontanaLewis and Clark County Area, MontanaLewis and Clark National Forest Area, MontanaLiberty County, MontanaLolo National Forest Area, MontanaMadison County Area, MontanaMcCone County, MontanaMeagher County Area, MontanaMissoula County Area, MontanaMusselshell County, MontanaPark County Area, MontanaPetroleum County, MontanaPhillips County Area, MontanaPowder River Area, MontanaPowell County Area, MontanaPrairie County, MontanaRed Rock Lakes Area - Part of Beaverhead County, MontanaRichland County, MontanaRoosevelt and Daniels Counties, MontanaRosebud County Area and Part of Big Horn County, MontanaSanders and Parts of Lincoln and Flathead Counties, MontanaSheridan County, MontanaSilver Bow County Area and Parts of Beaverhead and Jefferson Counties, MontanaStillwater County Area, MontanaSweet Grass County Area, MontanaToole County, MontanaTreasure County, MontanaUpper Flathead Valley Area, MontanaValley County, MontanaWheatland County Area, MontanaWibaux County, MontanaYellowstone County, Montana