Soil series profile
Olton soil series
Olton is a well drained soil with a clay loam surface, mapped on 1,783,097 acres in 34 counties across 2 states. Hydrologic group C.
- Drainage class
- Well drained 100% of mapped acres
- Hydrologic group
- C 100% of mapped acres
- Typical topsoil pH
- 7.2 neutral · range 7.1–7.2
- Mapped area
- 1.8M acres in 34 counties, 2 states
Typical Olton profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–8 in (Ap) | Clay loam | 7.2 | 31% | 34% | 2.8% |
| 8–31 in (Bt) | Clay loam | 7.6 | 39% | 34% | 0.95% |
| 31–48 in (Btk1) | Clay loam | 8.3 | 38% | 36% | 0.6% |
| 48–80 in (Btk2) | Clay loam | 8.4 | 39% | 38% | 0.1% |
What this means
What Olton soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Olton soils is neutral: pH 7.2 (most land between 7.1 and 7.2), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 100% of mapped Olton acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is clay loam (79% of mapped Olton acres).
100% of mapped Olton acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
On 100% 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 100% of the acres in mapped Olton soils very limited, 0% somewhat limited and 0% not limited.
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 Olton soil is found
Mapped acres
Olton is mapped in Texas and New Mexico.
| County | Acres | Share of county land |
|---|---|---|
| Parmer County, TX | 240,424 | 42.5% |
| Curry County, NM | 181,176 | 20.5% |
| Castro County, TX | 148,451 | 25.8% |
| Hale County, TX | 119,050 | 18.5% |
| Lubbock County, TX | 111,500 | 19.4% |
| Crosby County, TX | 110,890 | 19.2% |
| Garza County, TX | 95,124 | 16.6% |
| Quay County, NM | 90,711 | 4.9% |
| Deaf Smith County, TX | 84,849 | 8.9% |
| Borden County, TX | 77,931 | 13.5% |
| Lamb County, TX | 66,487 | 10.2% |
| Dickens County, TX | 61,612 | 10.6% |
| Floyd County, TX | 48,810 | 7.7% |
| Randall County, TX | 45,573 | 7.7% |
| Howard County, TX | 36,952 | 6.4% |
| Swisher County, TX | 33,128 | 5.8% |
| Oldham County, TX | 29,976 | 3.1% |
| Lipscomb County, TX | 29,787 | 5.0% |
| Briscoe County, TX | 29,029 | 5.0% |
| Armstrong County, TX | 28,408 | 4.9% |
| Potter County, TX | 23,645 | 4.0% |
| Gray County, TX | 18,259 | 3.1% |
| Hockley County, TX | 14,118 | 2.4% |
| Carson County, TX | 11,313 | 1.9% |
| Roberts County, TX | 10,602 | 1.8% |
| Martin County, TX | 8,573 | 1.5% |
| Wheeler County, TX | 7,916 | 1.4% |
| Donley County, TX | 6,887 | 1.2% |
| Lynn County, TX | 6,236 | 1.1% |
| Bailey County, TX | 4,581 | 0.9% |
| Irion County, TX | 842 | 0.1% |
| Motley County, TX | 179 | 0.0% |
| Glasscock County, TX | 55 | 0.0% |
| Hemphill County, TX | 24 | 0.0% |
Septic absorption fields
NRCS rating, share of Olton acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 100.0% |
Drainage, water table and flooding
Share of Olton 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 0–2% (median 0%).
- Topsoil organic matter
- Median 2.8%.
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 | 0.0% |
| C: slow infiltration | 100.0% |
| 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% |
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 Olton (component kind "Series") in SSURGO: 1,783,097 acres.
- Method
- Shares are by mapped acres of Olton components. The profile comes from the single largest Olton component. Full methodology.