Soil series profile
Mermill soil series
Mermill is a very poorly drained soil with a loam surface, mapped on 112,346 acres in 23 counties across 3 states. Hydrologic group C/D.
- Drainage class
- Very poorly drained 90% of mapped acres
- Hydrologic group
- C/D 62% of mapped acres
- Typical topsoil pH
- 6.5 slightly acidic · range 6.3–6.5
- Mapped area
- 112k acres in 23 counties, 3 states
Typical Mermill profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–9 in (H1) | Loam | 6.5 | 20% | 42% | 4.5% |
| 9–32 in (H2) | Sandy clay loam | 6.7 | 27% | 56% | 0.75% |
| 32–60 in (H3) | Clay loam | 7.5 | 39% | 26% | 0.25% |

What this means
What Mermill soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Mermill soils is slightly acidic: pH 6.5 (most land between 6.3 and 6.5), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 94% of mapped Mermill acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is loam (83% of mapped Mermill acres).
95% of mapped Mermill 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 94% 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 94% 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 94% of the acres in mapped Mermill soils very limited, 0% somewhat limited and 0% not limited (6% 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.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Mermill soil is found
Mapped acres
Mermill is mapped in Ohio, Indiana and Michigan.
| County | Acres | Share of county land |
|---|---|---|
| Wood County, OH | 23,646 | 6.0% |
| Fulton County, OH | 20,400 | 7.9% |
| Henry County, OH | 15,513 | 5.8% |
| Sandusky County, OH | 7,947 | 3.0% |
| Williams County, OH | 7,833 | 2.9% |
| Lucas County, OH | 7,771 | 3.5% |
| Defiance County, OH | 6,716 | 2.6% |
| Putnam County, OH | 6,002 | 1.9% |
| Whitley County, IN | 4,369 | 2.0% |
| Lorain County, OH | 3,386 | 1.1% |
| Hancock County, OH | 2,500 | 0.7% |
| Seneca County, OH | 1,444 | 0.4% |
| Paulding County, OH | 1,138 | 0.4% |
| Wyandot County, OH | 958 | 0.4% |
| Allen County, IN | 785 | 0.2% |
| Pulaski County, IN | 558 | 0.2% |
| Cuyahoga County, OH | 350 | 0.1% |
| Erie County, OH | 321 | 0.2% |
| Van Wert County, OH | 313 | 0.1% |
| Lenawee County, MI | 266 | 0.1% |
| Monroe County, MI | 72 | 0.0% |
| Allen County, OH | 59 | 0.0% |
| Auglaize County, OH | 0 | 0.0% |
Septic absorption fields
NRCS rating, share of Mermill acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 94.1% |
| Not rated | 5.9% |
Drainage, water table and flooding
Share of Mermill acres
- Depth to seasonal high water table
- About 6 inches (median where reported); within 18 inches on 94% of acres.
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 0–1% (median 1%).
- Topsoil organic matter
- Median 4.5%.
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 | 0.0% |
| Poorly drained | 5.1% |
| Very poorly drained | 89.5% |
| Not rated | 5.5% |
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) | 11.5% |
| A/D: D as is, A if drained | 0.0% |
| B/D: D as is, B if drained | 20.7% |
| C/D: D as is, C if drained | 61.9% |
| Not rated | 5.9% |
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 Mermill (component kind "Series") in SSURGO: 112,346 acres.
- Method
- Shares are by mapped acres of Mermill components. The profile comes from the single largest Mermill component. Full methodology.