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.

#3207 by mapped area fine-loamy Mollic Ochraqualfs (Alfisols)

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

Typical Mermill soil profile by depth 0 in 10 in 20 in 30 in 40 in 50 in 0–9 in · H1 · pH 6.5 · 20% clay Loam 9–32 in · H2 · pH 6.7 · 27% clay Sandy clay loam 32–60 in · H3 · pH 7.5 · 39% clay Clay loam
Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).
Show as a table
Typical Mermill horizons (representative values)
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%

Representative values from the most extensive Mermill map unit (Mermill loam, survey area OH051). Other map units of this series vary within the series range.

Hands holding dark garden soil
Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

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.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Mermill soil is found

Mapped acres

Mermill is mapped in Ohio, Indiana and Michigan.

Counties with the most mapped Mermill soil
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

Not limited 0%
Somewhat limited 0%
Very limited 94%
Not rated 6%
Septic tank absorption field rating across mapped Mermill acres. Scale 0 to 100% of mapped land.
Show as a table
Septic tank absorption field rating across mapped Mermill acres.
CategoryShare of acres
Not limited0.0%
Somewhat limited0.0%
Very limited94.1%
Not rated5.9%

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

Excessively drained 0%
Somewhat excessively drained 0%
Well drained 0%
Moderately well drained 0%
Somewhat poorly drained 0%
Poorly drained 5%
Very poorly drained 90%
Not rated 6%
Drainage class across mapped Mermill acres. Scale 0 to 100% of mapped land.
Show as a table
Drainage class across mapped Mermill acres.
CategoryShare of acres
Excessively drained0.0%
Somewhat excessively drained0.0%
Well drained0.0%
Moderately well drained0.0%
Somewhat poorly drained0.0%
Poorly drained5.1%
Very poorly drained89.5%
Not rated5.5%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%
B: moderate infiltration 0%
C: slow infiltration 0%
D: very slow infiltration (clayey, shallow or wet) 12%
A/D: D as is, A if drained 0%
B/D: D as is, B if drained 21%
C/D: D as is, C if drained 62%
Not rated 6%
Hydrologic soil group across mapped Mermill acres. Scale 0 to 100% of mapped land.
Show as a table
Hydrologic soil group across mapped Mermill acres.
CategoryShare of acres
A: fast infiltration (mostly sandy or gravelly)0.0%
B: moderate infiltration0.0%
C: slow infiltration0.0%
D: very slow infiltration (clayey, shallow or wet)11.5%
A/D: D as is, A if drained0.0%
B/D: D as is, B if drained20.7%
C/D: D as is, C if drained61.9%
Not rated5.9%

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.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Mermill.