Soil series profile
Plano soil series
Plano is a well drained soil with a silt loam surface, mapped on 381,447 acres in 37 counties across 3 states. Hydrologic group B.
- Drainage class
- Well drained 96% of mapped acres
- Hydrologic group
- B >99% of mapped acres
- Typical topsoil pH
- 6.7 neutral · range 6.5–6.7
- Mapped area
- 381k acres in 37 counties, 3 states
Typical Plano profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–11 in (Ap) | Silt loam | 6.7 | 23% | 10% | 4% |
| 11–41 in (Bt1) | Silty clay loam | 6.2 | 30% | 7% | 0.6% |
| 41–46 in (2Bt2) | Loam | 7.6 | 23% | 43% | 0.25% |
| 46–79 in (2C) | Sandy loam | 8.0 | 12% | 63% | 0.25% |
What this means
What Plano soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Plano soils is neutral: pH 6.7 (most land between 6.5 and 6.7), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers >99% of mapped Plano acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (>99% of mapped Plano acres).
100% of mapped Plano acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.
For a septic system
For conventional septic absorption fields, NRCS rates 96% of the acres in mapped Plano soils very limited, 4% somewhat limited and 0% not limited.
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.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Plano soil is found
Mapped acres
Plano is mapped in Wisconsin, Illinois and Indiana.
| County | Acres | Share of county land |
|---|---|---|
| Dane County, WI | 54,833 | 7.1% |
| Rock County, WI | 48,004 | 10.4% |
| Walworth County, WI | 41,017 | 11.6% |
| Columbia County, WI | 38,666 | 7.9% |
| Dodge County, WI | 27,563 | 4.9% |
| Logan County, IL | 20,744 | 5.3% |
| Green Lake County, WI | 19,963 | 8.8% |
| Ogle County, IL | 16,255 | 3.4% |
| Fond du Lac County, WI | 15,366 | 3.3% |
| Winnebago County, IL | 10,651 | 3.4% |
| LaSalle County, IL | 10,310 | 1.5% |
| Henry County, IL | 9,593 | 1.9% |
| Bureau County, IL | 8,289 | 1.5% |
| Menard County, IL | 7,084 | 3.6% |
| Stephenson County, IL | 7,078 | 2.0% |
| McLean County, IL | 6,934 | 0.9% |
| Stark County, IL | 6,401 | 3.5% |
| Macon County, IL | 5,428 | 1.5% |
| Tazewell County, IL | 4,239 | 1.1% |
| Boone County, IL | 3,460 | 2.0% |
| Mason County, IL | 3,244 | 1.0% |
| Kendall County, IL | 2,956 | 1.5% |
| Marshall County, IL | 2,537 | 1.0% |
| De Witt County, IL | 2,109 | 0.8% |
| Vermilion County, IL | 1,817 | 0.3% |
| Peoria County, IL | 1,446 | 0.4% |
| Piatt County, IL | 1,424 | 0.5% |
| Winnebago County, WI | 1,120 | 0.4% |
| Gallatin County, IL | 523 | 0.3% |
| Vermillion County, IN | 446 | 0.3% |
| Woodford County, IL | 414 | 0.1% |
| Kenosha County, WI | 408 | 0.2% |
| Edgar County, IL | 325 | 0.1% |
| Douglas County, IL | 321 | 0.1% |
| Mercer County, IL | 193 | 0.1% |
| Sangamon County, IL | 145 | 0.0% |
| Racine County, WI | 142 | 0.1% |
Septic absorption fields
NRCS rating, share of Plano acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 3.5% |
| Very limited | 95.8% |
| Not rated | 0.7% |
Drainage, water table and flooding
Share of Plano acres
- Depth to seasonal high water table
- About 3.3 feet (39 in) (median where reported).
- Flooding
- Mapped as flooding on <1% of acres (0% occasional, 0% frequent).
- Slope
- Typically 1–4% (median 4%).
- Topsoil organic matter
- Median 4%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 96.1% |
| Moderately well drained | 3.9% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 0.0% |
| B: moderate infiltration | 99.6% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| A/D: D as is, A if drained | 0.0% |
| B/D: D as is, B if drained | 0.0% |
| C/D: D as is, C if drained | 0.0% |
| Not rated | 0.4% |
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
- All map unit components named Plano (component kind "Series") in SSURGO: 381,447 acres.
- Method
- Shares are by mapped acres of Plano components. The profile comes from the single largest Plano component. Full methodology.