Harmon County, Oklahoma
The most common soil here is Westill, on about 8% of the land: a clay loam, firm and a little sticky. Woodward and Grandfield come next.
About 96% of the land drains well.
USDA rates 89% of the land very limited for a standard septic drain field, and 40% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 7% of the land floods occasionally or more, and bedrock lies within 40 inches under 33% of it.
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 Harmon County, Oklahoma, 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 Well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Inceptisols — young soils with minimal horizon development but more than Entisols. 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 Harmon County, Oklahoma. 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 |
|---|---|---|---|---|---|
| Tilvern clay loam, 1 to 3 percent slopes | 22K | Well drained | D | Very limited | Very limited |
| Westill clay loam, 1 to 3 percent slopes | 22K | Well drained | D | Very limited | Very limited |
| Woodward-Quinlan complex, 5 to 12 percent slopes | 19K | Well drained | C | Somewhat limited | Very limited |
| Vernon-Knoco complex, cool, 1 to 12 percent slopes | 18K | Well drained | D | Somewhat limited | Very limited |
| Grandfield loamy sand, 0 to 3 percent slopes | 15K | Well drained | B | Not limited | Very limited |
| Aspermont silt loam, 1 to 3 percent slopes | 14K | Well drained | B | Not limited | Somewhat limited |
| Knoco, Rock outcrop, and Cottonwood soils, 2 to 20 percent slopes | 14K | Well drained | D | Very limited | Very limited |
| Knoco-Badland complex, dry, 1 to 12 percent slopes | 11K | Well drained | D | Very limited | Very limited |
| Madge loam, 1 to 3 percent slopes | 11K | Well drained | B | Not limited | Very limited |
| Springer and Devol loamy sands, 0 to 3 percent slopes | 9K | Well drained | A | Not limited | Very limited |
| Tipton loam, 0 to 1 percent slopes | 9K | Well drained | B | Somewhat limited | Somewhat limited |
| Woodward-Quinlan complex, 3 to 5 percent slopes | 8K | Well drained | C | Somewhat limited | Very limited |
| Talpa-Aspermont-Rock outcrop complex, 1 to 8 percent slopes | 8K | Well drained | D | Very limited | Very limited |
| Westill clay loam, 0 to 1 percent slopes | 7K | Well drained | D | Very limited | Very limited |
| Devol and Springer loamy sands, 3 to 8 percent slopes | 6K | Well drained | A | Not limited | Very limited |
| Quinlan-Rock outcrop complex, 12 to 45 percent slopes | 6K | Well drained | D | Very limited | Very limited |
| Vernon clay loam, 3 to 5 percent slopes, eroded | 6K | Well drained | D | Very limited | Very limited |
| Water | 6K | D | Not rated | Not rated | |
| La Casa silty clay loam, 1 to 3 percent slopes | 5K | Well drained | C | Somewhat limited | Very limited |
| Tipton fine sandy loam, 0 to 1 percent slopes | 5K | Well drained | B | Somewhat 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 40% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 89% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.