Soil series profile
Nappanee soil series
Nappanee is a somewhat poorly drained soil with a silty clay loam surface, mapped on 305,830 acres in 36 counties across 4 states. Hydrologic group C/D.
- Drainage class
- Somewhat poorly drained >99% of mapped acres
- Hydrologic group
- C/D 64% of mapped acres
- Typical topsoil pH
- 6.2 slightly acidic · range 6.0–6.5
- Mapped area
- 306k acres in 36 counties, 4 states
Typical Nappanee profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–8 in (H1) | Silty clay loam | 6.2 | 36% | 8% | 2% |
| 8–34 in (H2) | Silty clay | 6.5 | 53% | 3% | 0.5% |
| 34–60 in (H3) | Silty clay | 7.9 | 43% | 8% | 0.25% |

What this means
What Nappanee soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Nappanee soils is slightly acidic: pH 6.2 (most land between 6.0 and 6.5), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers >99% of mapped Nappanee acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (39% of mapped Nappanee acres).
>99% of mapped Nappanee acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.
For lawns and yards
On >99% of mapped acres, 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 >99% of mapped acres, often in spring. Basements, sump pumps and lawns in low spots feel it first.
For a septic system
For conventional septic absorption fields, NRCS rates >99% of the acres in mapped Nappanee soils very limited, 0% 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 Nappanee soil is found
Mapped acres
Nappanee is mapped in Ohio, Michigan, Illinois and Indiana.
| County | Acres | Share of county land |
|---|---|---|
| Paulding County, OH | 28,816 | 10.8% |
| Ottawa County, OH | 28,489 | 17.6% |
| Lenawee County, MI | 24,290 | 5.1% |
| Logan County, OH | 21,424 | 7.3% |
| Wood County, OH | 18,327 | 4.6% |
| Putnam County, OH | 17,189 | 5.6% |
| Union County, OH | 15,936 | 5.7% |
| Van Wert County, OH | 14,889 | 5.7% |
| Henry County, OH | 14,520 | 5.4% |
| Allen County, IN | 14,429 | 3.5% |
| Seneca County, OH | 10,915 | 3.1% |
| Defiance County, OH | 10,652 | 4.0% |
| Sandusky County, OH | 9,566 | 3.7% |
| Lake County, IL | 9,455 | 3.4% |
| Washtenaw County, MI | 9,332 | 2.1% |
| Fulton County, OH | 9,243 | 3.6% |
| LaSalle County, IL | 6,845 | 1.0% |
| Wayne County, MI | 6,114 | 1.6% |
| Adams County, IN | 5,369 | 2.5% |
| Williams County, OH | 4,789 | 1.8% |
| Monroe County, MI | 4,725 | 1.3% |
| Lucas County, OH | 4,538 | 2.1% |
| Wyandot County, OH | 3,309 | 1.3% |
| Hancock County, OH | 3,209 | 0.9% |
| Cook County, IL | 1,773 | 0.3% |
| Oceana County, MI | 1,185 | 0.3% |
| Will County, IL | 1,134 | 0.2% |
| LaGrange County, IN | 1,049 | 0.4% |
| Grundy County, IL | 999 | 0.4% |
| Iroquois County, IL | 951 | 0.1% |
| Livingston County, IL | 937 | 0.1% |
| Allen County, OH | 893 | 0.3% |
| Kendall County, IL | 291 | 0.1% |
| McHenry County, IL | 241 | 0.1% |
| Vermilion County, IL | 6 | 0.0% |
| Hardin County, OH | 2 | 0.0% |
Septic absorption fields
NRCS rating, share of Nappanee acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 99.1% |
| Not rated | 0.9% |
Drainage, water table and flooding
Share of Nappanee acres
- Depth to seasonal high water table
- About 1.2 feet (14 in) (median where reported); within 18 inches on >99% of acres.
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 0–4% (median 1%).
- Topsoil organic matter
- Median 2%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 0.0% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 99.1% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
| Not rated | 0.9% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 0.0% |
| B: moderate infiltration | 0.0% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 34.7% |
| 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 | 64.4% |
| Not rated | 0.9% |
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 Nappanee (component kind "Series") in SSURGO: 305,830 acres.
- Method
- Shares are by mapped acres of Nappanee components. The profile comes from the single largest Nappanee component. Full methodology.