St. Croix County, Wisconsin
The most common soil here is Santiago, on about 9% of the land: a silt loam, smooth, like flour. Sattre and Freeon come next.
About 65% of the land drains well, and 17% stays wet for long stretches; groundwater comes within two feet of the surface under 24% of it.
USDA rates 83% of the land very limited for a standard septic drain field, and 46% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 5% of the land floods occasionally or more, and bedrock lies within 40 inches under 8% 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 St. Croix County, Wisconsin, 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 St. Croix County, Wisconsin. 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 |
|---|---|---|---|---|---|
| Santiago silt loam, 2 to 6 percent slopes | 32K | Well drained | B | Not limited | Somewhat limited |
| Freeon silt loam, 2 to 6 percent slopes | 23K | Moderately well drained | C/D | Very limited | Very limited |
| Magnor silt loam, 0 to 4 percent slopes | 21K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Skyberg silt loam, 0 to 3 percent slopes | 16K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Pillot silt loam, 0 to 3 percent slopes | 16K | Well drained | B | Not limited | Very limited |
| Sattre silt loam, 2 to 6 percent slopes | 15K | Well drained | B | Not limited | Very limited |
| Vlasaty silt loam, 2 to 6 percent slopes | 15K | Moderately well drained | C | Very limited | Very limited |
| Amery loam, 6 to 12 percent slopes, eroded | 15K | Well drained | C | Somewhat limited | Very limited |
| Jewett silt loam, 2 to 6 percent slopes | 14K | Well drained | C | Somewhat limited | Somewhat limited |
| Santiago silt loam, 6 to 12 percent slopes, eroded | 13K | Well drained | B | Somewhat limited | Somewhat limited |
| Jewett silt loam, sandy substratum, 2 to 6 percent slopes | 13K | Well drained | C | Not limited | Very limited |
| Burkhardt-Sattre complex, 6 to 12 percent slopes, eroded | 11K | Excessively drained | A | Somewhat limited | Very limited |
| Antigo silt loam, 2 to 6 percent slopes | 10K | Well drained | B | Not limited | Very limited |
| Water | 10K | Not rated | Not rated | ||
| Burkhardt-Sattre complex, 12 to 30 percent slopes, eroded | 9K | Excessively drained | A | Very limited | Very limited |
| Freeon silt loam, heavy substratum, 2 to 6 percent slopes | 8K | Moderately well drained | B/D | Very limited | Very limited |
| Amery loam, 12 to 20 percent slopes, eroded | 8K | Well drained | C | Very limited | Very limited |
| Fluvaquents | 7K | Somewhat poorly drained | B | Very limited | Very limited |
| Sattre loam, 2 to 6 percent slopes | 7K | Well drained | B | Not limited | Very limited |
| Sattre silt loam, 0 to 2 percent slopes | 7K | Well drained | B | Not 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 46% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 83% 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.