State soil summary
Soil types in Wisconsin
The most widespread soil series in Wisconsin are Magnor, Pence, Padus. Pick a county below, or enter a ZIP code for the county you live in.
- Well or moderately well drained
- 65% of mapped land
- Typical topsoil pH
- 5.9 moderately acidic · most land 5.0–6.8
- Septic fields very limited
- 92% 0% not limited
- Subject to flooding
- 7% of land, any frequency
Wisconsin counties
11 county reports, by population
| County | Most common soil | Well drained | Topsoil pH | Septic very limited |
|---|---|---|---|---|
| Milwaukee County | Ozaukee | 31% | 6.7 | 61% |
| Dane County | Plano | 74% | 6.5 | 89% |
| Waukesha County | Fox | 63% | 6.8 | 90% |
| Brown County | Kewaunee | 61% | 6.7 | 89% |
| Racine County | Ozaukee | 51% | 6.5 | 94% |
| Outagamie County | Hortonville | 51% | 6.7 | 86% |
| Winnebago County | Kewaunee | 43% | 6.7 | 92% |
| Kenosha County | Ozaukee | 49% | 6.5 | 92% |
| Rock County | Kidder | 77% | 6.5 | 85% |
| Marathon County | Withee | 45% | 5.9 | 89% |
| Washington County | Theresa | 65% | 7.0 | 82% |
What this means
What Wisconsin soils mean for gardens, lawns and septic systems
For gardens
Typical topsoil in Wisconsin is moderately acidic: pH 5.9 (most land between 5.0 and 6.8). Many vegetables grow well here, and some gardens benefit from a little lime. Test before adding any.
Loamy topsoil (loam, silt loam and similar) covers 66% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (39% of the land).
65% of the land is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
On 57% of the land, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.
A seasonal high water table comes within 18 inches of the surface on 37% of the land, often in spring. Basements, sump pumps and lawns in low spots feel it first.
For septic systems
For conventional septic absorption fields, NRCS rates 92% of the land in Wisconsin very limited, 5% somewhat limited and 0% not limited (3% not rated, such as urban land, pits or water).
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.
Flooding is mapped on 7% of the land (2% occasional, 4% frequent).
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Statewide mix
Share of all mapped land
Drainage
Show as a table
| Category | Share of land |
|---|---|
| Excessively drained | 8.5% |
| Somewhat excessively drained | 5.1% |
| Well drained | 36.1% |
| Moderately well drained | 15.1% |
| Somewhat poorly drained | 14.3% |
| Poorly drained | 7.4% |
| Very poorly drained | 11.3% |
| Not rated | 2.2% |
Septic absorption fields
Show as a table
| Category | Share of land |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 4.9% |
| Very limited | 91.9% |
| Not rated | 3.2% |
Topsoil pH
Show as a table
| Category | Share of land |
|---|---|
| Strongly acidic (below 5.5) | 18.5% |
| Moderately to slightly acidic (5.5–6.4) | 43.9% |
| Near neutral (6.5–7.3) | 26.0% |
| Alkaline (7.4 and up) | 0.5% |
| Not reported | 11.1% |
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
- Wisconsin: 34,625,052 acres of mapped land in 72 counties, pooled (not an average of county figures).
- Method
- Shares are by mapped land area: each map unit’s acres in the county times each soil component’s percentage. Open water is excluded. Topsoil values use the first mineral horizon of each component. Full methodology.