St. Clair County Soil Data
St. Clair County, Michigan
Avg pH
6.1
Texture
Muck
Drainage
Very poorly drained
Organic Matter
7.0%
Hydrologic Group
B/D
Data Story
About Soil in St. Clair County, Michigan
Histosols and Ancient Muck
St. Clair County is characterized by Histosols—organic-rich soils often called 'muck'—with an average pH of 6.10. This pH is quite favorable compared to the Michigan state average of 5.30 and is nearly in line with the national median of 6.5. These soils represent ancient lake beds and river floodplains.
Dense Mix with High Silt
The soil consists of 54.4% sand, 27.8% silt, and 16.8% clay. The relatively high clay and silt percentages give the soil a heavy feel and excellent nutrient-holding capacity. However, the muck texture can become quite slippery and difficult to work when excessively wet.
Organic Riches for High Yields
At 7.02% organic matter, these soils are far richer than the national average of 2.0%. The available water capacity is 0.175 in/in, which provides a steady supply of moisture to plants during the summer. This fertility profile supports the intensive sod and vegetable farming common in the region.
Poor Drainage Requires Care
Classified as very poorly drained and falling into hydrologic group B/D, these soils naturally hold water. High water tables can be a challenge for home foundations and basement construction in certain parts of the county. For farming, these areas often rely on sophisticated ditch and tile systems to manage saturation.
Lush Growth in Zone 6a
The 6a climate combined with moisture-retentive soils makes St. Clair perfect for leafy greens, onions, and celery. Native perennials and moisture-loving flowers also thrive in this environment. If you have a spot with these rich soils, your garden has incredible potential for lush, rapid growth.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Group B — Moderate Runoff
Moderately deep, moderately well-drained soils with moderate infiltration rates. Good balance of drainage and water retention.
Drainage Class
Very poorly drained
Water is removed so slowly that free water remains at or on the surface most of the year. Typically wetland soils.
Soil Profile
Dominant texture: Muck
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Frequently Asked Questions
What type of soil does St. Clair County have?
St. Clair County's soil is classified as Muck. This indicates the relative proportions of sand, silt, and clay — 54% sand, 28% silt, and 17% clay. Sandy soils drain quickly but may need more frequent irrigation and fertilization.
Is St. Clair County's soil acidic or alkaline?
St. Clair County's soil has a pH of 6.1, which is moderately acidic. This range suits many crops and is common across much of the eastern US.
What is the drainage class for St. Clair County?
St. Clair County has a dominant drainage class of "Very poorly drained." Poorly drained soils retain water for extended periods, which can limit crop choices and may require tile drainage or raised beds.
What crops or plants grow well in St. Clair County's soil?
Based on St. Clair County's Muck texture, pH of 6.1, and Very poorly drained, the soil is well suited for vegetables, grains, and most field crops, rice, cranberries, and other water-tolerant species.
What USDA soil order is found in St. Clair County?
St. Clair County's dominant soil order is Histosols. Histosols are organic soils (peatlands and bogs) with very high organic matter content. They form in wet, poorly drained environments.
Planning your lawn? View lawn care data for St. Clair County on LawnByCounty.com →
Other Counties in Michigan
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.