Audubon County, Iowa
The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). 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 Audubon County, Iowa.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Judson-Colo-Ackmore complex, 2 to 5 percent slopes | 52K | Poorly drained | C/D | Very limited | Very limited |
| Marshall silty clay loam, 9 to 14 percent slopes, eroded | 40K | Well drained | C | Somewhat limited | Very limited |
| Marshall silty clay loam, 5 to 9 percent slopes, eroded | 39K | Well drained | C | Somewhat limited | Very limited |
| Exira silty clay loam, 9 to 14 percent slopes, eroded | 19K | Well drained | C | Somewhat limited | Very limited |
| Marshall silty clay loam, 2 to 5 percent slopes, eroded | 14K | Well drained | C | Somewhat limited | Very limited |
| Marshall silty clay loam, 2 to 5 percent slopes | 10K | Well drained | C | Somewhat limited | Very limited |
| Shelby-Adair clay loams, deep loess, 9 to 14 percent slopes, eroded | 10K | Well drained | C | Somewhat limited | Very limited |
| Zook silty clay loam, 0 to 2 percent slopes, occasionally flooded | 9K | Poorly drained | D | Very limited | Very limited |
| Colo silty clay loam, deep loess, 0 to 2 percent slopes, occasionally flooded | 6K | Poorly drained | C/D | Very limited | Very limited |
| Shelby clay loam, deep loess, 14 to 18 percent slopes, severely eroded | 6K | Well drained | C | Very limited | Very limited |
| Marshall silty clay loam, 14 to 20 percent slopes, eroded | 6K | Well drained | C | Very limited | Very limited |
| Exira silty clay loam, 5 to 9 percent slopes, eroded | 6K | Well drained | C | Somewhat limited | Very limited |
| Judson silty clay loam, deep loess, 2 to 5 percent slopes | 5K | Well drained | C | Somewhat limited | Very limited |
| Ackmore silt loam, 0 to 2 percent slopes, occasionally flooded | 5K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Shelby-Adair clay loams, deep loess, 14 to 18 percent slopes, eroded | 5K | Well drained | C | Very limited | Very limited |
| Shelby-Adair clay loams, deep loess, 14 to 18 percent slopes, severely eroded | 4K | Well drained | C | Very limited | Very limited |
| Shelby-Adair clay loams, deep loess, 9 to 14 percent slopes, severely eroded | 4K | Well drained | C | Somewhat limited | Very limited |
| Dockery-Quiver silt loams, deep loess, 0 to 2 percent slopes, occasionally flooded | 4K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Shelby clay loam, deep loess, 9 to 14 percent slopes, eroded | 3K | Well drained | C | Somewhat limited | Very limited |
| Shelby clay loam, deep loess, 18 to 25 percent slopes, severely eroded | 3K | Well drained | C | Very limited | Very limited |
What This Means
Building & Foundations
About 40% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 100% 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.