Soil series profile
Grandfield soil series
Grandfield is a well drained soil with a loamy sand surface, mapped on 803,674 acres in 47 counties across 3 states. Hydrologic group B.
- Drainage class
- Well drained 100% of mapped acres
- Hydrologic group
- B 93% of mapped acres
- Typical topsoil pH
- 7.0 neutral · range 5.8–7.0
- Mapped area
- 804k acres in 47 counties, 3 states
Typical Grandfield profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–7 in (Ap) | Loamy sand | 5.8 | 8% | 86% | 0.75% |
| 7–27 in (Bt1) | Sandy clay loam | 6.8 | 24% | 56% | 0.5% |
| 27–40 in (Bt2) | Sandy clay loam | 7.1 | 21% | 57% | 0.5% |
| 40–80 in (BC) | Fine sandy loam | 7.5 | 13% | 77% | 0.25% |
What this means
What Grandfield soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Grandfield soils is neutral: pH 7.0 (most land between 5.8 and 7.0), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 56% of mapped Grandfield acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (58% of mapped Grandfield acres).
100% of mapped Grandfield acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.
For a septic system
For conventional septic absorption fields, NRCS rates 87% of the acres in mapped Grandfield soils very limited, 3% somewhat limited and 0% not limited (10% 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 Grandfield soil is found
Mapped acres
Grandfield is mapped in Texas, Oklahoma and Kansas.
| County | Acres | Share of county land |
|---|---|---|
| Wheeler County, TX | 161,299 | 27.6% |
| Washita County, OK | 60,314 | 9.4% |
| Beckham County, OK | 57,857 | 10.1% |
| Lipscomb County, TX | 50,051 | 8.4% |
| Roger Mills County, OK | 46,382 | 6.3% |
| Hemphill County, TX | 44,541 | 7.6% |
| Dewey County, OK | 39,878 | 6.2% |
| Hardeman County, TX | 25,044 | 5.6% |
| Harmon County, OK | 22,705 | 6.7% |
| Clay County, TX | 22,660 | 3.3% |
| Childress County, TX | 21,774 | 4.8% |
| Tillman County, OK | 20,322 | 3.6% |
| Haskell County, TX | 19,069 | 3.3% |
| Greer County, OK | 18,827 | 4.6% |
| Jackson County, OK | 17,321 | 3.4% |
| Young County, TX | 16,908 | 2.9% |
| Archer County, TX | 16,022 | 2.8% |
| King County, TX | 14,877 | 2.5% |
| Harper County, OK | 12,525 | 1.9% |
| Knox County, TX | 12,428 | 2.3% |
| Woodward County, OK | 11,848 | 1.4% |
| Kent County, TX | 10,113 | 1.8% |
| Ellis County, OK | 9,971 | 1.3% |
| Collingsworth County, TX | 9,883 | 1.7% |
| Throckmorton County, TX | 9,145 | 1.6% |
| Baylor County, TX | 6,510 | 1.2% |
| Shackelford County, TX | 6,044 | 1.0% |
| Donley County, TX | 5,870 | 1.0% |
| Dickens County, TX | 5,403 | 0.9% |
| Major County, OK | 4,757 | 0.8% |
| Kiowa County, OK | 4,266 | 0.7% |
| Blaine County, OK | 3,712 | 0.6% |
| Wilbarger County, TX | 3,675 | 0.6% |
| Woods County, OK | 2,438 | 0.3% |
| Foard County, TX | 2,175 | 0.4% |
| Gray County, TX | 1,521 | 0.3% |
| Wichita County, TX | 1,441 | 0.4% |
| Alfalfa County, OK | 1,195 | 0.2% |
| Custer County, OK | 997 | 0.2% |
| Hall County, TX | 502 | 0.1% |
| Cotton County, OK | 318 | 0.1% |
| Clark County, KS | 276 | 0.0% |
| Cottle County, TX | 276 | 0.0% |
| Floyd County, TX | 204 | 0.0% |
| Stonewall County, TX | 182 | 0.0% |
| Comanche County, KS | 133 | 0.0% |
| Armstrong County, TX | 15 | 0.0% |
Septic absorption fields
NRCS rating, share of Grandfield acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 2.9% |
| Very limited | 87.0% |
| Not rated | 10.0% |
Drainage, water table and flooding
Share of Grandfield 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 2–6% (median 2%).
- Topsoil organic matter
- Median 0.8%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 100.0% |
| 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 | 92.8% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| 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 | 7.2% |
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 Grandfield (component kind "Series") in SSURGO: 803,674 acres.
- Method
- Shares are by mapped acres of Grandfield components. The profile comes from the single largest Grandfield component. Full methodology.