Decatur County Soil Data
Decatur County, Tennessee
Avg pH
5.2
Texture
Silt loam
Drainage
Moderately well drained
Organic Matter
1.3%
Hydrologic Group
C/D
Data Story
About Soil in Decatur County, Tennessee
Acidic Alfisols along the river
Decatur County features silt loam soils categorized as Alfisols. The average pH of 5.18 is lower than both the Tennessee state average of 5.35 and the national median of 6.5.
Sand and silt provide easy workability
With 27.7% sand and 50.0% silt, this soil is relatively easy to till and work. The 20.3% clay content helps ensure the soil doesn't lose nutrients too quickly during heavy rains.
State-average water capacity for plants
The organic matter content of 1.35% is lower than the state's 2.44% average. However, the available water capacity of 0.168 in/in is nearly identical to the state average, providing reliable moisture for vegetation.
Variable drainage requires careful planning
The soil is moderately well drained but falls into the C/D hydrologic group. This indicates that water can move slowly through the profile, making runoff management important for agricultural fields.
Forestry and farming in zone 7b
This soil-climate combination is excellent for timber production and row crops like corn. Adding organic compost can help boost the lower fertility levels for a thriving home garden.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Group C — Moderate-High Runoff
Soils with slow infiltration rates, often with a layer that impedes downward water movement. Higher clay content restricts drainage.
Drainage Class
Moderately well drained
Water is removed somewhat slowly. May have a slowly permeable layer or seasonal water table.
Soil Profile
Dominant texture: Silt loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Frequently Asked Questions
What type of soil does Decatur County have?
Decatur County's soil is classified as Silt loam. This indicates the relative proportions of sand, silt, and clay — 28% sand, 50% silt, and 20% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Decatur County's soil acidic or alkaline?
Decatur County's soil has a low pH of 5.2, which is strongly acidic. Acidic soils benefit from lime applications to raise pH and improve nutrient availability.
What is the drainage class for Decatur County?
Decatur County has a dominant drainage class of "Moderately well drained." Well-drained soils allow excess water to move through quickly, reducing waterlogging risk and supporting most field and garden crops.
What crops or plants grow well in Decatur County's soil?
Based on Decatur County's Silt loam texture, pH of 5.2, and Moderately well drained, the soil is well suited for acid-loving plants like blueberries and azaleas, row crops and vegetable gardens, most annual and perennial crops.
What USDA soil order is found in Decatur County?
Decatur County's dominant soil order is Alfisols. Alfisols are moderate to high base-status soils with a clay-enriched subsoil. They support productive forests and cropland across temperate regions.
Planning your lawn? View lawn care data for Decatur County on LawnByCounty.com →
Other Counties in Tennessee
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.