Allen County, Ohio
The most common soil here is Blount, on about 38% of the land: a silt loam, smooth, like flour. Pewamo and Glynwood come next.
About 3% of the land drains well, and 78% stays wet for long stretches; groundwater comes within two feet of the surface under 94% of it.
USDA rates 97% of the land very limited for a standard septic drain field, and 96% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 6% of the land floods occasionally or more.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Allen County, Ohio, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Somewhat poorly drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Alfisols — moderately leached forest soils with a clay-enriched subsoil. This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Allen County, Ohio. Search your address to find the exact soil composition, drainage, and series details at your specific location.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Pewamo silty clay loam, 0 to 1 percent slopes | 65K | Very poorly drained | C/D | Very limited | Very limited |
| Blount silt loam, ground moraine, 2 to 4 percent slopes | 38K | Somewhat poorly drained | D | Very limited | Very limited |
| Blount silt loam, ground moraine, 0 to 2 percent slopes | 31K | Somewhat poorly drained | D | Very limited | Very limited |
| Blount silt loam, end moraine, 2 to 4 percent slopes | 29K | Somewhat poorly drained | D | Very limited | Very limited |
| Glynwood silt loam, ground moraine, 2 to 6 percent slopes | 6K | Moderately well drained | D | Very limited | Very limited |
| Hoytville silty clay loam, 0 to 1 percent slopes | 6K | Very poorly drained | C/D | Very limited | Very limited |
| Glynwood-Urban land complex, 2 to 6 percent slopes | 6K | Moderately well drained | C/D | Very limited | Very limited |
| Glynwood silt loam, end moraine, 2 to 6 percent slopes | 6K | Moderately well drained | D | Very limited | Very limited |
| Blount silt loam, end moraine, 0 to 2 percent slopes | 6K | Somewhat poorly drained | D | Very limited | Very limited |
| Sloan silty clay loam, till substratum, 0 to 1 percent slopes, frequently flooded | 4K | Very poorly drained | B/D | Very limited | Very limited |
| Glynwood clay loam, end moraine, 2 to 6 percent slopes, eroded | 3K | Moderately well drained | D | Very limited | Very limited |
| Cygnet loam, 0 to 3 percent slopes | 3K | Moderately well drained | B/D | Very limited | Very limited |
| Houcktown loam, 2 to 6 percent slopes | 3K | Moderately well drained | C/D | Very limited | Very limited |
| Glynwood clay loam, ground moraine, 2 to 6 percent slopes, eroded | 3K | Moderately well drained | D | Very limited | Very limited |
| Knoxdale silt loam, 0 to 2 percent slopes, occasionally flooded | 3K | Well drained | B | Very limited | Very limited |
| Shoals silt loam, till substratum, 0 to 1 percent slopes, occasionally flooded | 3K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Water | 2K | Not rated | Not rated | ||
| Glynwood clay loam, 6 to 12 percent slopes, eroded | 2K | Moderately well drained | D | Very limited | Very limited |
| Shawtown loam, 2 to 6 percent slopes | 2K | Moderately well drained | C | Somewhat limited | Very limited |
| Glynwood clay loam, ground moraine, 6 to 12 percent slopes, eroded | 2K | Moderately well drained | D | Very limited | Very limited |
Soil Orders in This Area
The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.
What This Means
Building & Foundations
About 96% of soils are rated "very limited" for dwellings with basements. Specific challenges include poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 97% of soils are rated "very limited" for septic absorption fields. Poorly drained soils can't absorb septic effluent effectively. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Many soils hold water for extended periods. Raised beds are highly recommended to improve drainage for vegetables. Well-adapted native plants and water-loving species will do best in natural conditions.