Soil series profile
Darnell soil series
Darnell is a excessively drained soil with a fine sandy loam surface, mapped on 542,210 acres in 37 counties across 3 states. Hydrologic group D.
- Drainage class
- Excessively drained 36% of mapped acres
- Hydrologic group
- D 96% of mapped acres
- Typical topsoil pH
- 6.4 slightly acidic · range 6.2–6.4
- Mapped area
- 542k acres in 37 counties, 3 states
Typical Darnell profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–8 in (A) | Fine sandy loam | 6.4 | 12% | 55% | 1.5% |
| 8–10 in (E) | Fine sandy loam | 6.2 | 10% | 55% | 0.3% |
| 10–16 in (Bw) | Fine sandy loam | 6.4 | 12% | 65% | 0.3% |
| 16–26 in (Cr) | Bedrock | Not reported | Not reported | Not reported | Not reported |
What this means
What Darnell soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Darnell soils is slightly acidic: pH 6.4 (most land between 6.2 and 6.4), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 96% of mapped Darnell acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (89% of mapped Darnell acres).
65% of mapped Darnell acres is excessively or somewhat excessively drained: water moves through fast, so gardens need more frequent watering in dry spells.
For lawns and yards
On 96% 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.
For a septic system
For conventional septic absorption fields, NRCS rates 96% of the acres in mapped Darnell soils very limited, 0% somewhat limited and 0% not limited (4% 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 Darnell soil is found
Mapped acres
Darnell is mapped in Oklahoma, Kansas and Texas.
| County | Acres | Share of county land |
|---|---|---|
| Lincoln County, OK | 96,539 | 15.8% |
| Caddo County, OK | 49,753 | 6.1% |
| Seminole County, OK | 41,904 | 10.4% |
| Oklahoma County, OK | 32,959 | 7.3% |
| Pontotoc County, OK | 29,246 | 6.4% |
| Logan County, OK | 29,212 | 6.2% |
| Cleveland County, OK | 27,506 | 8.0% |
| Okfuskee County, OK | 25,314 | 6.4% |
| Grady County, OK | 24,103 | 3.4% |
| Chautauqua County, KS | 23,217 | 5.7% |
| Pottawatomie County, OK | 21,856 | 4.4% |
| Stephens County, OK | 19,222 | 3.4% |
| Jack County, TX | 17,693 | 3.0% |
| Payne County, OK | 15,090 | 3.5% |
| Canadian County, OK | 11,540 | 2.0% |
| Elk County, KS | 10,464 | 2.5% |
| Carter County, OK | 8,347 | 1.6% |
| Garvin County, OK | 7,128 | 1.4% |
| Clay County, TX | 6,616 | 1.0% |
| Montgomery County, KS | 6,218 | 1.5% |
| Wilson County, KS | 5,016 | 1.4% |
| Greenwood County, KS | 4,483 | 0.6% |
| Archer County, TX | 4,308 | 0.7% |
| Noble County, OK | 3,107 | 0.7% |
| Love County, OK | 2,848 | 0.9% |
| Jefferson County, OK | 2,498 | 0.5% |
| Johnston County, OK | 2,329 | 0.6% |
| Marshall County, OK | 2,308 | 1.0% |
| Neosho County, KS | 2,281 | 0.6% |
| Pawnee County, OK | 1,939 | 0.5% |
| Woodson County, KS | 1,937 | 0.6% |
| Washington County, OK | 1,862 | 0.7% |
| McClain County, OK | 1,531 | 0.4% |
| Comanche County, OK | 756 | 0.1% |
| Creek County, OK | 706 | 0.1% |
| Young County, TX | 209 | 0.0% |
| Throckmorton County, TX | 164 | 0.0% |
Septic absorption fields
NRCS rating, share of Darnell acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 95.8% |
| Not rated | 4.2% |
Drainage, water table and flooding
Share of Darnell acres
- Depth to seasonal high water table
- None reported within about 6.5 feet (median where reported).
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 4–19% (median 8%).
- Topsoil organic matter
- Median 1.5%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 35.7% |
| Somewhat excessively drained | 29.2% |
| Well drained | 35.1% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
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) | 96.1% |
| 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 | 0.0% |
| Not rated | 3.9% |
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 Darnell (component kind "Series") in SSURGO: 542,210 acres.
- Method
- Shares are by mapped acres of Darnell components. The profile comes from the single largest Darnell component. Full methodology.