County soil summary

Soil types in Tulsa County, Oklahoma

The most widespread soils are Dennis, Radley and Okemah; the most common drainage class is somewhat poorly drained (45% of the land), and typical topsoil pH is 6.1.

Mapped soil survey data 363,000 acres of mapped land · 47 named soil series

Well or moderately well drained
44%
of land · state 87%
Typical topsoil pH
6.1
slightly acidic · state 6.5
Septic fields very limited
87%
of land · state 77%
Subject to flooding
24%
of land, any frequency · state 14%

Most common soils in Tulsa County

Share of mapped land

A county is a patchwork of many soils. These 8 cover 56% of the mapped land; 47 named soil series are mapped here in all.

Most common soils in Tulsa County by share of mapped land
Soil Share of land Drainage Topsoil pH
Dennis 21.3% Somewhat poorly drained 5.6
Radley 6.4% Moderately well drained 6.5
Okemah 6.0% Somewhat poorly drained 6.5
Urban landLand type, not a soil series 5.5% — —
Coweta 5.0% Well drained 5.8
Wynona 4.2% Somewhat poorly drained 5.8
Eram 4.0% Moderately well drained 6.1
Choska 3.7% Well drained 7.0

Drainage and pH for a series are its typical values across all its mapped acres nationwide. A dash means the row is not a soil series.

What this means

What the soils in Tulsa County mean for gardens, lawns and septic systems

For your garden

Typical topsoil in Tulsa County is slightly acidic: pH 6.1 (most land between 5.6 and 6.7), the range most vegetables, flowers and lawn grasses prefer.

Loamy topsoil (loam, silt loam and similar) covers 82% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (45% of the land).

48% of the land is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.

For your lawn and yard

On 75% of the land, 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 87% of the land in Tulsa County very limited, 9% somewhat limited and 0% not limited (4% not rated, such as urban land, pits or water).

Statewide, 77% of the land is very limited, so Tulsa County is more restrictive than typical.

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 24% of the land (10% occasional, 7% frequent).

Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Drainage

How long the soil stays wet

The most common drainage class is somewhat poorly drained (45%). 44% of the land is moderately well drained or better, compared with 87% across Oklahoma.

Excessively drained 0%
Somewhat excessively drained 1%
Well drained 30%
Moderately well drained 13%
Somewhat poorly drained 45%
Poorly drained 3%
Very poorly drained 0%
Not rated 8%
Natural drainage class, share of mapped land in Tulsa County. Scale 0 to 100% of mapped land.
Show as a table
Natural drainage class, share of mapped land in Tulsa County.
CategoryTulsa CountyOklahoma
Excessively drained0.0%2.0%
Somewhat excessively drained1.0%5.7%
Well drained29.7%68.0%
Moderately well drained12.9%11.6%
Somewhat poorly drained44.5%8.8%
Poorly drained3.4%1.4%
Very poorly drained0.0%0.3%
Not rated8.4%2.3%

Septic absorption fields

NRCS rating for conventional drain fields

The rating looks at the soil from 24 to 60 inches deep: permeability, depth to a seasonal water table or bedrock, flooding and slope. “Very limited” means at least one feature is unfavorable enough that a conventional field is hard to make work.

Not limited 0%
Somewhat limited 9%
Very limited 87%
Not rated 4%
Septic tank absorption field rating, share of mapped land in Tulsa County. Scale 0 to 100% of mapped land.
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Septic tank absorption field rating, share of mapped land in Tulsa County.
CategoryTulsa CountyOklahoma
Not limited0.0%1.1%
Somewhat limited8.9%15.4%
Very limited86.8%77.2%
Not rated4.4%6.2%

Rain, runoff and water table

Hydrologic soil group, flooding, seasonal water table

Hydrologic soil group

How fast rain soaks in when the soil is already wet. Group A soaks in fastest, D slowest.

A: fast infiltration (mostly sandy or gravelly) 2%
B: moderate infiltration 21%
C: slow infiltration 7%
D: very slow infiltration (clayey, shallow or wet) 37%
A/D: D as is, A if drained <1%
B/D: D as is, B if drained 0%
C/D: D as is, C if drained 31%
Not rated 2%
Hydrologic soil group, share of mapped land in Tulsa County. Scale 0 to 100% of mapped land.
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Hydrologic soil group, share of mapped land in Tulsa County.
CategoryTulsa CountyOklahoma
A: fast infiltration (mostly sandy or gravelly)2.0%11.4%
B: moderate infiltration20.8%27.5%
C: slow infiltration6.5%20.9%
D: very slow infiltration (clayey, shallow or wet)37.0%32.5%
A/D: D as is, A if drained0.3%0.2%
B/D: D as is, B if drained0.0%0.4%
C/D: D as is, C if drained31.2%4.5%
Not rated2.1%2.6%

Flooding

No flooding 75%
Rare or very rare 8%
Occasional 10%
Frequent or very frequent 7%
Not reported <1%
Most frequent flooding class in any month, share of mapped land in Tulsa County. Scale 0 to 100% of mapped land.
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Most frequent flooding class in any month, share of mapped land in Tulsa County.
CategoryTulsa CountyOklahoma
No flooding75.2%85.4%
Rare or very rare7.6%2.5%
Occasional10.1%7.2%
Frequent or very frequent6.6%4.7%
Not reported0.6%0.2%

Seasonal high water table

Within 18 inches at some time of year 20%
18 inches to 3.3 feet 34%
Deeper than 3.3 feet or none reported 45%
Not reported <1%
Shallowest depth to a saturated zone in any month, share of mapped land in Tulsa County. Scale 0 to 100% of mapped land.
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Shallowest depth to a saturated zone in any month, share of mapped land in Tulsa County.
CategoryTulsa CountyOklahoma
Within 18 inches at some time of year19.9%9.6%
18 inches to 3.3 feet34.2%6.8%
Deeper than 3.3 feet or none reported45.4%83.5%
Not reported0.6%0.1%

Topsoil pH and texture

First mineral layer of each soil

Typical topsoil pH is 6.1 (slightly acidic); 80% of rated land falls between 5.6 and 6.7. Median topsoil organic matter is 2%.

Strongly acidic (below 5.5) 1%
Moderately to slightly acidic (5.5–6.4) 57%
Near neutral (6.5–7.3) 29%
Alkaline (7.4 and up) 4%
Not reported 10%
Topsoil pH band, share of mapped land in Tulsa County. Scale 0 to 100% of mapped land.
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Topsoil pH band, share of mapped land in Tulsa County.
CategoryTulsa CountyOklahoma
Strongly acidic (below 5.5)1.3%9.9%
Moderately to slightly acidic (5.5–6.4)57.1%31.4%
Near neutral (6.5–7.3)28.6%31.4%
Alkaline (7.4 and up)3.5%19.4%
Not reported9.5%7.9%

Texture

Sandy 4%
Loamy (loam, silt loam and similar) 82%
Clayey (40%+ clay) 5%
Organic (muck or peat) 0%
Not reported (rock, urban land, etc.) 10%
Topsoil texture group, share of mapped land in Tulsa County. Scale 0 to 100% of mapped land.
Show as a table
Topsoil texture group, share of mapped land in Tulsa County.
CategoryTulsa CountyOklahoma
Sandy4.0%10.0%
Loamy (loam, silt loam and similar)81.9%78.7%
Clayey (40%+ clay)4.6%3.4%
Organic (muck or peat)0.0%0.0%
Not reported (rock, urban land, etc.)9.5%7.9%

Most common surface textures: silt loam 45% · loam 10% · silty clay loam 10% · fine sandy loam 8% · very fine sandy loam 7%.

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
Tulsa County, Oklahoma (FIPS 40143): 363,368 acres of mapped land, 12,306 acres of open water excluded. State comparisons pool all mapped land in Oklahoma.
Method
Shares are by mapped land area: each map unit’s acres in the county times each soil component’s percentage. Open water is excluded. Topsoil values use the first mineral horizon of each component. Full methodology.

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