Knox County, Illinois
The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). 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 Knox County, Illinois.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Ipava silt loam, 0 to 2 percent slopes | 75K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Osco silt loam, 2 to 5 percent slopes | 66K | Well drained | B | Somewhat limited | Somewhat limited |
| Rozetta silt loam, 5 to 10 percent slopes, eroded | 29K | Well drained | B | Somewhat limited | Somewhat limited |
| Osco silt loam, 5 to 10 percent slopes, eroded | 26K | Well drained | B | Somewhat limited | Somewhat limited |
| Rozetta silt loam, 2 to 5 percent slopes | 23K | Well drained | B | Somewhat limited | Somewhat limited |
| Osco silt loam, 2 to 5 percent slopes, eroded | 20K | Well drained | B | Somewhat limited | Somewhat limited |
| Hickory silt loam, cool mesic, 18 to 35 percent slopes, eroded | 19K | Well drained | B | Very limited | Very limited |
| Lawson silt loam, cool mesic, 0 to 2 percent slopes, frequently flooded | 16K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Sable silty clay loam, 0 to 2 percent slopes | 16K | Poorly drained | B/D | Very limited | Very limited |
| Greenbush silt loam, 2 to 5 percent slopes | 13K | Well drained | B | Somewhat limited | Somewhat limited |
| Clarksdale silt loam, 0 to 2 percent slopes | 12K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Hickory silt loam, cool mesic, 10 to 18 percent slopes, eroded | 10K | Well drained | B | Somewhat limited | Somewhat limited |
| Elco silt loam, 10 to 18 percent slopes, eroded | 9K | Moderately well drained | C | Very limited | Very limited |
| Lenzburg silty clay loam, 20 to 60 percent slopes | 9K | Well drained | C | Very limited | Very limited |
| Hickory silt loam, cool mesic, 35 to 60 percent slopes | 7K | Well drained | B | Very limited | Very limited |
| Marseilles silt loam, 35 to 60 percent slopes | 7K | Well drained | D | Very limited | Very limited |
| Elkhart silt loam, 5 to 10 percent slopes, eroded | 6K | Well drained | B | Somewhat limited | Somewhat limited |
| Sawmill silt loam, 0 to 2 percent slopes, frequently flooded, overwash | 6K | Poorly drained | B/D | Very limited | Very limited |
| Marseilles silt loam, 18 to 35 percent slopes | 6K | Well drained | D | Very limited | Very limited |
| Fayette silt loam, glaciated, 5 to 10 percent slopes, eroded | 5K | Well drained | B | Somewhat limited | Somewhat limited |
What This Means
Building & Foundations
About 48% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 48% of soils have significant septic limitations, while others are more suitable. A perc test is essential — conditions vary across the area.
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.