Soil series profile
Sengtown soil series
Sengtown is a well drained soil with a gravelly silt loam surface, mapped on 626,425 acres in 36 counties across 2 states. Hydrologic group B.
- Drainage class
- Well drained >99% of mapped acres
- Hydrologic group
- B 96% of mapped acres
- Typical topsoil pH
- 6.3 slightly acidic · range 5.3–6.3
- Mapped area
- 626k acres in 36 counties, 2 states
Typical Sengtown profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–9 in (H1) | Gravelly silt loam | 5.3 | 20% | 27% | 2% |
| 9–15 in (H2) | Gravelly silty clay loam | 5.3 | 32% | 20% | 0.25% |
| 15–60 in (H3) | Gravelly clay | 5.3 | 50% | 22% | 0.25% |
What this means
What Sengtown soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Sengtown soils is slightly acidic: pH 6.3 (most land between 5.3 and 6.3), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers >99% of mapped Sengtown acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is gravelly silt loam (95% of mapped Sengtown acres).
>99% of mapped Sengtown acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.
For a septic system
For conventional septic absorption fields, NRCS rates 57% of the acres in mapped Sengtown soils very limited, 43% somewhat limited and 0% not limited.
Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Sengtown soil is found
Mapped acres
Sengtown is mapped in Tennessee and Kentucky.
| County | Acres | Share of county land |
|---|---|---|
| Dickson County, TN | 168,049 | 53.6% |
| Montgomery County, TN | 103,362 | 30.1% |
| Robertson County, TN | 66,981 | 22.1% |
| Hickman County, TN | 57,916 | 14.8% |
| Cheatham County, TN | 51,548 | 26.7% |
| Overton County, TN | 22,089 | 8.0% |
| Stewart County, TN | 21,734 | 7.4% |
| Sumner County, TN | 20,491 | 6.1% |
| Benton County, TN | 19,506 | 7.7% |
| Macon County, TN | 14,116 | 7.2% |
| Warren County, TN | 13,818 | 5.0% |
| Houston County, TN | 13,392 | 10.5% |
| Williamson County, TN | 12,328 | 3.3% |
| Lincoln County, TN | 9,555 | 2.6% |
| Humphreys County, TN | 8,302 | 2.5% |
| Putnam County, TN | 4,329 | 1.7% |
| Davidson County, TN | 4,063 | 1.3% |
| Coffee County, TN | 2,548 | 0.9% |
| Maury County, TN | 1,774 | 0.5% |
| Smith County, TN | 1,349 | 0.7% |
| Calloway County, KY | 1,272 | 0.6% |
| Decatur County, TN | 1,264 | 0.6% |
| Clay County, TN | 1,238 | 0.8% |
| Henry County, TN | 976 | 0.3% |
| Cannon County, TN | 855 | 0.5% |
| Marshall County, KY | 733 | 0.3% |
| Jackson County, TN | 656 | 0.3% |
| DeKalb County, TN | 616 | 0.3% |
| White County, TN | 490 | 0.2% |
| Moore County, TN | 414 | 0.5% |
| Lawrence County, TN | 192 | 0.0% |
| Lewis County, TN | 174 | 0.1% |
| Wayne County, TN | 128 | 0.0% |
| Bedford County, TN | 125 | 0.0% |
| Van Buren County, TN | 38 | 0.0% |
| Wilson County, TN | 3 | 0.0% |
Septic absorption fields
NRCS rating, share of Sengtown acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 43.4% |
| Very limited | 56.5% |
| Not rated | 0.1% |
Drainage, water table and flooding
Share of Sengtown acres
- Depth to seasonal high water table
- None reported within about 6.5 feet (median where reported).
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 8–45% (median 16%).
- Topsoil organic matter
- Median 1.8%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 99.9% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
| Not rated | 0.1% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 0.0% |
| B: moderate infiltration | 96.4% |
| C: slow infiltration | 3.5% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| A/D: D as is, A if drained | 0.0% |
| B/D: D as is, B if drained | 0.0% |
| C/D: D as is, C if drained | 0.0% |
| Not rated | 0.1% |
Sources & data dates
- Source
- USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
- Data date
- SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
- Scope
- All map unit components named Sengtown (component kind "Series") in SSURGO: 626,425 acres.
- Method
- Shares are by mapped acres of Sengtown components. The profile comes from the single largest Sengtown component. Full methodology.