Lyon and Trigg Counties, Kentucky
The most common soil here is Hammack, on about 15% of the land: a silt loam, smooth, like flour. Brandon and Baxter come next.
About 69% of the land drains well; groundwater comes within two feet of the surface under 16% of it.
USDA rates 65% of the land very limited for a standard septic drain field, and 59% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 11% 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 Lyon and Trigg Counties, Kentucky, 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 Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Lyon and Trigg Counties, Kentucky. 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 |
|---|---|---|---|---|---|
| Water | 69K | Not rated | Not rated | ||
| Baxter-Hammack complex, 20 to 30 percent slopes | 55K | Well drained | B | Very limited | Very limited |
| Hammack-Baxter complex, 6 to 12 percent slopes | 48K | Well drained | B | Somewhat limited | Somewhat limited |
| Brandon-Saffell complex, 20 to 50 percent slopes | 42K | Well drained | B | Very limited | Very limited |
| Hammack-Baxter complex, 12 to 20 percent slopes | 31K | Well drained | B | Very limited | Very limited |
| Nicholson silt loam, 2 to 6 percent slopes | 26K | Moderately well drained | C/D | Very limited | Very limited |
| Nolin silt loam | 26K | Well drained | B | Very limited | Very limited |
| Brandon silt loam, 6 to 12 percent slopes | 26K | Well drained | B | Somewhat limited | Very limited |
| Crider silt loam, 2 to 6 percent slopes | 14K | Well drained | B | Somewhat limited | Somewhat limited |
| Brandon silt loam, 12 to 20 percent slopes | 13K | Well drained | B | Very limited | Very limited |
| Crider-Pembroke silt loams, 6 to 12 percent slopes | 11K | Well drained | B | Somewhat limited | Somewhat limited |
| Clifty gravelly silt loam | 11K | Well drained | A | Very limited | Very limited |
| Lindside silt loam | 10K | Moderately well drained | B/D | Very limited | Very limited |
| Hammack-Baxter complex, 6 to 12 percent slopes, severely eroded | 9K | Well drained | B | Somewhat limited | Somewhat limited |
| Lax silt loam, 2 to 6 percent slopes | 9K | Moderately well drained | C/D | Very limited | Very limited |
| Lax silt loam, 6 to 12 percent slopes | 8K | Moderately well drained | C/D | Very limited | Very limited |
| Hammack silt loam, 2 to 6 percent slopes | 8K | Well drained | B | Somewhat limited | Somewhat limited |
| Hammack-Baxter complex, 12 to 20 percent slopes, severely eroded | 8K | Well drained | B | Very limited | Very limited |
| Nicholson silt loam, 6 to 12 percent slopes | 7K | Moderately well drained | C/D | Very limited | Very limited |
| Saffell very gravelly silt loam, 20 to 60 percent slopes | 7K | Well drained | B | 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 59% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 65% 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.