Decatur County, Indiana
The most common soil here is Fincastle, on about 15% of the land: a silt loam, smooth, like flour. Miami and Cyclone come next.
About 18% of the land drains well, and 49% stays wet for long stretches; groundwater comes within two feet of the surface under 73% of it.
USDA rates 99% of the land very limited for a standard septic drain field, and 94% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 9% of the land floods occasionally or more, and bedrock lies within 40 inches under 1% 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 Decatur County, Indiana, 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 Moderately well drained and the dominant hydrologic group is B/D (varies with drainage). The most common soil order is Alfisols — moderately leached forest soils with a clay-enriched subsoil. 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 Decatur County, Indiana. 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 |
|---|---|---|---|---|---|
| Fincastle silt loam, New Castle Till Plain, 0 to 2 percent slopes | 37K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Cyclone silt loam, 0 to 2 percent slopes | 27K | Poorly drained | B/D | Very limited | Very limited |
| Cobbsfork silt loam, 0 to 1 percent slopes | 16K | Poorly drained | C/D | Very limited | Very limited |
| Avonburg silt loam, 0 to 2 percent slopes | 15K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Williamstown silt loam, 2 to 6 percent slopes, eroded | 13K | Moderately well drained | C/D | Very limited | Very limited |
| Miami clay loam, 6 to 12 percent slopes, severely eroded | 13K | Moderately well drained | C | Very limited | Very limited |
| Xenia silt loam, 2 to 4 percent slopes | 12K | Moderately well drained | B/D | Very limited | Very limited |
| Miami silt loam, 2 to 6 percent slopes, eroded | 12K | Moderately well drained | C | Very limited | Very limited |
| Nabb silt loam, 2 to 6 percent slopes, eroded | 11K | Moderately well drained | C/D | Very limited | Very limited |
| Orrville silt loam, frequently flooded | 10K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Cincinnati silt loam, 6 to 12 percent slopes, severely eroded | 8K | Well drained | D | Very limited | Very limited |
| Xenia silt loam, Southern Ohio Till Plain, 0 to 2 percent slopes | 7K | Moderately well drained | C/D | Very limited | Very limited |
| Chagrin loam, frequently flooded | 6K | Well drained | B | Very limited | Very limited |
| Russell silt loam, 2 to 6 percent slopes | 6K | Well drained | B | Somewhat limited | Very limited |
| Crosby silt loam, New Castle Till Plain, 0 to 2 percent slopes | 5K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Lobdell silt loam, frequently flooded | 5K | Moderately well drained | B/D | Very limited | Very limited |
| Hennepin loam, 25 to 50 percent slopes | 4K | Well drained | C | Very limited | Very limited |
| Miami clay loam, 12 to 18 percent slopes, severely eroded | 2K | Moderately well drained | C | Very limited | Very limited |
| Hickory loam, 18 to 25 percent slopes, eroded | 2K | Well drained | B | Very limited | Very limited |
| Fincastle silt loam, Tipton Till Plain, 2 to 4 percent slopes | 2K | Somewhat poorly drained | B/D | 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 94% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 99% 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.