Dawson County Soil Data
Dawson County, Montana
USDA SSURGO / PHZMAvg pH
7.5
Texture
Loam
Drainage
N/A
Organic Matter
2.1%
Hydrologic Group
N/A
Data Story
About Soil in Dawson County, Montana
Slightly Alkaline Eastern Montana Soil
Dawson County has an average pH of 7.52, which is more alkaline than the national median of 6.5. This figure also slightly exceeds the Montana state average of 7.43. These levels are common for the region and generally require minimal lime but may need sulfur for acid-loving plants.
A Silty Foundation for Farming
The soil mix contains 35.1% sand, 42.3% silt, and 22.6% clay. This silty profile makes the ground relatively easy to work while maintaining enough clay to hold onto essential nutrients. It provides a stable base for both native grasses and cultivated crops.
Strong Water Retention Capabilities
Organic matter sits at 2.14%, which is higher than the national average of 2.0% but below the state's 2.54%. Interestingly, its available water capacity of 0.168 in/in is better than the state average of 0.165. This helps the county maintain a soil score of 41.2, nearing the state average.
Managing Water in Silty Terrain
Official drainage class data is currently unavailable, but the high silt content suggests moderate water movement. Farmers should be aware that silty soils can sometimes crust over after heavy rains, potentially impacting seed emergence. Proper residue management can help mitigate these surface issues.
Hardy Options for Zone 4a
In USDA Hardiness Zone 4a, growers should focus on crops that can withstand late spring frosts. Wheat, barley, and hardy root vegetables perform well in this soil and climate combination. The slightly above-average water capacity gives your plants a fighting chance during dry spells.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Hydrologic group data not available.
Drainage Class
Drainage class data not available.
Soil Profile
Dominant texture: Loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Alkaline Soil Detected
Your county's average pH is 7.5. These products help acidify soil for better nutrient uptake.
Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Dawson County have?
Dawson County's soil is classified as Loam. This indicates the relative proportions of sand, silt, and clay — 35% sand, 42% silt, and 23% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Dawson County's soil acidic or alkaline?
Dawson County's soil has a pH of 7.5, which is mildly to moderately alkaline. Sulfur amendments can lower pH if needed.
What is the drainage class for Dawson County?
Drainage class data is not currently available for Dawson County.
What crops or plants grow well in Dawson County's soil?
Based on Dawson County's Loam texture, pH of 7.5, and drainage class, the soil is well suited for drought-tolerant crops and native grasses, row crops and vegetable gardens.
What USDA soil order is found in Dawson County?
The dominant USDA soil order for Dawson County is not currently available in our dataset.
Soil & Planting Advisory: Dawson County
Soil Verdict
Dawson County is in USDA hardiness zone 4a, a cold climate zone. where winter lows can reach -30°F. Soils here experience deep freeze cycles that can disrupt structure, kill shallow roots, and slow microbial activity for months each year.
Planting Guidance
Focus on cold-hardy perennials, native grasses, and conifers. The short growing window favors plants with low heat requirements. With extreme winter lows, any marginally hardy plants need heavy mulch and wind protection. Always match plant selections to the specific microclimate of your property — low spots, slopes, and wind exposure can shift effective hardiness by half a zone.
Soil Implications
Deep winter freezing can create soil heaving that pushes shallow-rooted plants out of the ground; add 3-4 inches of organic mulch each fall. Soil drainage is critical — frozen, waterlogged soil kills roots faster than cold alone. When soil temperatures drop below freezing, microbial nitrogen cycling stops; spring fertilization is more effective than late-fall application.
Regional Context
Dawson County closely matches the Montana average hardiness conditions. The zone range of 4a-4b within the county means soil and planting decisions should account for local elevation and topography.
Planning your lawn? View lawn care data for Dawson County on LawnByCounty.com →
Other Counties in Montana
Soil data sourced from USDA SSURGO via Soil Data Access. Data is informational only and should not be used as a substitute for on-site soil testing. Contact your local NRCS office for site-specific soil information.