Soil series profile
Port soil series
Port is a well drained soil with a silt loam surface, mapped on 723,252 acres in 46 counties across 3 states. Hydrologic group B.
- Drainage class
- Well drained 100% of mapped acres
- Hydrologic group
- B >99% of mapped acres
- Typical topsoil pH
- 7.0 neutral · range 6.5–7.8
- Mapped area
- 723k acres in 46 counties, 3 states
Typical Port profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–8 in (Ap) | Silt loam | 7.0 | 20% | 11% | 2% |
| 8–28 in (A) | Silt loam | 7.0 | 21% | 11% | 2% |
| 28–43 in (Bk) | Silty clay loam | 8.2 | 34% | 6% | 0.5% |
| 43–75 in (BCk) | Silty clay loam | 8.2 | 33% | 6% | 0.5% |
What this means
What Port soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Port soils is neutral: pH 7.0 (most land between 6.5 and 7.8), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 97% of mapped Port acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (55% of mapped Port acres).
100% of mapped Port 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 97% of the acres in mapped Port soils very limited, <1% somewhat limited and 0% not limited (3% 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.
Flooding is mapped on 100% of the acres (75% occasional, 24% frequent).
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Port soil is found
Mapped acres
Port is mapped in Oklahoma, Texas and Kansas.
| County | Acres | Share of county land |
|---|---|---|
| Cotton County, OK | 55,421 | 13.5% |
| Grady County, OK | 49,746 | 7.1% |
| Stephens County, OK | 48,178 | 8.6% |
| Noble County, OK | 37,314 | 8.0% |
| Jefferson County, OK | 34,665 | 7.2% |
| Clay County, TX | 34,563 | 5.0% |
| Canadian County, OK | 32,905 | 5.8% |
| Kay County, OK | 32,209 | 5.5% |
| Kiowa County, OK | 31,569 | 4.9% |
| Garfield County, OK | 30,689 | 4.5% |
| Caddo County, OK | 28,744 | 3.5% |
| Garvin County, OK | 27,567 | 5.4% |
| Creek County, OK | 26,799 | 4.4% |
| Pottawatomie County, OK | 26,613 | 5.3% |
| Major County, OK | 22,822 | 3.8% |
| Archer County, TX | 22,126 | 3.8% |
| Kingfisher County, OK | 20,931 | 3.7% |
| Grant County, OK | 19,929 | 3.1% |
| McClain County, OK | 19,248 | 5.3% |
| Blaine County, OK | 18,401 | 3.1% |
| Alfalfa County, OK | 16,690 | 3.0% |
| Pawnee County, OK | 12,776 | 3.5% |
| Cleveland County, OK | 11,524 | 3.4% |
| Roger Mills County, OK | 9,267 | 1.3% |
| Washita County, OK | 9,046 | 1.4% |
| Harper County, KS | 8,706 | 1.7% |
| Wichita County, TX | 6,581 | 1.7% |
| Tillman County, OK | 5,953 | 1.0% |
| Comanche County, OK | 4,840 | 0.7% |
| Lincoln County, OK | 4,650 | 0.8% |
| Payne County, OK | 4,025 | 0.9% |
| Comanche County, KS | 1,990 | 0.4% |
| Dewey County, OK | 1,696 | 0.3% |
| Beckham County, OK | 1,361 | 0.2% |
| Woods County, OK | 768 | 0.1% |
| Custer County, OK | 707 | 0.1% |
| Oklahoma County, OK | 505 | 0.1% |
| Okfuskee County, OK | 498 | 0.1% |
| Seminole County, OK | 462 | 0.1% |
| Logan County, OK | 388 | 0.1% |
| Pontotoc County, OK | 137 | 0.0% |
| Murray County, OK | 125 | 0.0% |
| Love County, OK | 107 | 0.0% |
| Barber County, KS | 11 | 0.0% |
| Sumner County, KS | 1 | 0.0% |
| Osage County, OK | 0 | 0.0% |
Septic absorption fields
NRCS rating, share of Port acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.1% |
| Very limited | 97.0% |
| Not rated | 3.0% |
Drainage, water table and flooding
Share of Port acres
- Depth to seasonal high water table
- None reported within about 6.5 feet (median where reported).
- Flooding
- Mapped as flooding on 100% of acres (75% occasional, 24% frequent).
- Slope
- Typically 0–1% (median 0%).
- Topsoil organic matter
- Median 2%.
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 | 99.6% |
| 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 | 0.4% |
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 Port (component kind "Series") in SSURGO: 723,252 acres.
- Method
- Shares are by mapped acres of Port components. The profile comes from the single largest Port component. Full methodology.