LOCATION SEMINOLE                OK

Established Series
Rev. REM:JWF:JABG
09/2020

SEMINOLE SERIES

The Seminole series consists of deep, moderately well drained,
slowly permeable soils that formed in clayey sediments or material weathered from shale of Permian age. These soils occur on nearly level to gently sloping upland prairies.. Slopes range
from 0 to 5 percent. Mean annual temperature is 16 degrees C (61 degrees F), and mean annual precipitation is 1,041 mm (41 in).

TAXONOMIC CLASS: Fine, mixed, superactive, thermic Typic Natrustolls

TYPICAL PEDON: Seminole loam, on a west facing, concave, 2 percent slope in cropland, at an elevation of 295 m (969 ft) (Colors are for dry soil unless otherwise stated)

A--0 to 36 cm (0 to 14 in); grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; hard, friable; moderately acid, gradual wavy boundary. (Thickness of the A horizon is 15 to 46 cm [6 to 18 in])

BA--36 to 51 cm (14 to 20 in); brown (10YR 5/3) loam, brown (10YR 4/3) moist; few fine faint grayish brown and common fine distinct yellowish red and strong brown mottles that increase in size and number with depth; moderate medium and fine subangular blocky structure; very hard, firm; light brownish gray (10YR 6/2) and pale brown (10YR 6/3), silt coatings, less than 2 mm thick, surrounding peds; moderately acid; gradual smooth boundary. (Thickness of the BA horizon is 0 to 15 cm [0 to 6in])

Btn1--51 to 81 cm (20 to 32 in); pale brown (10YR 6/3) clay, brown (10YR 5/3) moist; common fine and medium prominent and distinct red (2.5YR 5/6), yellowish red (5YR 5/6), strong brown (7.5YR 5/6), yellowish brown (10YR 5/6), and grayish brown (10YR 5/2) mottles; moderate medium prismatic parting to moderate medium subangular blocky structure; very hard, very firm; nearly continuous clay films on faces of peds; few vertical faces have light brownish gray (10YR 6/2) silt coatings, less than 2 mm thick; moderately acid; gradual smooth boundary.

Btn2--81 to 122 cm (32 to 48 in); yellowish brown (10YR 5/4) clay, dark yellowish brown (10YR 4/4) moist; common coarse faint brown (10YR 4/3), yellowish brown (10YR 5/6), and grayish brown (10YR 5/2) mottles; moderate coarse subangular blocky structure; extremely hard, very firm; nearly continuous clay films on faces of peds; few soft dark bodies; moderately alkaline; diffuse smooth boundary. (Combined thickness of the Btn horizons is 41 to 97 cm [16 to 38 in])

BC--122 to 183 cm (48 to 72 in); brown (7.5YR 5/4) clay, brown (7.5YR4/4) moist; common fine and medium distinct grayish brown (10YR 5/2) and reddish yellow (7.5YR 6/6) mottles; weak coarse subangular blocky structure; extremely hard, very firm; patchy clay films on faces of peds; few soft dark bodies; few pitted calcium carbonate concretions; moderately alkaline.

TYPE LOCATION: Pottawatomie County, Oklahoma; about 7 miles east
and 2 miles north of Shawnee; about 200 feet east and 50 feet
south of the northwest corner of sec. 9, T. 10 N., R. 5 E.

USGS Topographic Quadrangle: Wayne, OK
Latitude: 35 degrees, 21 minutes, 43 seconds N
Longitude: 96 degrees, 47 minutes, 20 seconds W

Decimal Degrees:
Latitude: 35.3619560
Longitude: -96.7888430
Datim: WGS84

UTM Easting: 700895.00 m
UTM Northing: 3915427.00 m
UTM Zone: 14

RANGE IN CHARACTERISTICS:
Soil Moisture: udic ustic soil moisture regime
Thickness of the solum:: 152 cm to 200cm (60 to 80 in)
Thickness of mollic epipedon: 15 to 46 cm (6 to 18 in)
Depth to natric horizon: 51 to 61 cm (20 to 24 in)
Depth to argillic horizon: 51 to 61 cm (20 to 24 in)
Depth to abrupt texture change: 51 to 61 cm (20 to 24 in)
Depth of episaturation: 31 to 46 (12 to 18 in) from April to May

Particle-size control section: 51 to 101 cm (20 to 40 in)
Weighted average:
Clay content: 35 to 50 percent

A or Ap horizon:
Hue: 10YR or 7.5YR
Value: 5 or 4 dry, 3 moist
Chroma: 3 dry, 2 moist
Texture: loam or silt loam
Clay content: 12 to 18 percent
Reaction (pH): moderately acid to neutral (pH 5.6 to 7.0)

BA horizon:
Hue: 2.5YR, 7.5YR, or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 to 4 dry, 1 to 3 moist
Texture: loam, silt loam, or clay loam
Clay content: 18 to 35 percent
Reaction (pH): moderately acid to neutral (pH 5.6 to 7.0)
Exchangeable sodium percent: 5 to 10 percent

Btn horizons:
Hue: 2.5Y or 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 3 to 6 dry, 2 to 5 moist
Texture: clay, silty clay, or clay loam
Clay content: 35 to 50 percent
Reaction (pH): moderately acid to moderately alkaline (pH 5.6 to 7.9)
Exchangeable sodium percent: 15 to 25 percent
Mottles: when present 2.5YR 5/6, 7.5YR 5/6, 10YR 5/6, 10YR 5/2

BC horizon:
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 3 to 6 dry, 2 to 5 moist
Texture: clay, silty clay, or clay loam
Clay content: 35 to 50 percent
Reaction (pH): moderately acid to moderately alkaline (pH 5.6 to 7.9)
Exchangeable sodium percent: 15 to 25 percent

The C horizon: (when present)
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 3 to 6 dry, 2 to 5 moist
Texture: clay or clay loam
Clay content: 35 to 50 percent
Reaction: moderately acid to moderately alkaline (pH 5.6 to 7.9)
Some pedons are underlain with shale bedrock

COMPETING SERIES: These are the Deandale and Foard series.
Deandale soils: are dry for slightly longer periods, have a mollic epipedon more than 51 cm (20 in) thick and have Bt horizons with colors in hue of 5YR.
Foard soils: have montmorillonitic mineralogy and are dry for longer periods.

GEOGRAPHIC SETTING:
Parent material: Loamy or clayey residuum weathered from shale
Landscape: Uplands
Landform: Hillslopes
Slope: 0 to 5 percent
Mean annual air temperature: 16 to 18 degrees C (61 to 65 degrees F)
Mean annual precipitation: 889 to 1016 mm (35 to 40in)
Frost-free period: 181 to 240 days
Elevation: 244 to 366 m (800 to 1200ft)
Thornthwaite annual P-E Index Values: 55 to 64

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aydelotte and Chickasha series and they occur on similar areas of the landscape.
Aydelotte soils: lack a natric horizon.
Chickasha soils: have a fine-loamy control section and lack a natric horizon.

DRAINAGE AND PERMEABILITY:
Drainage: moderately well
Permeability: slow
Runoff: slow to medium
Seasonal water table: 31 to 46 cm (12 to 18 in) from April to May

USE AND VEGETATION:
Major uses: pasture and rangeland Principal crops are small grains, grain sorghum, soybeans, and peanuts.
Native vegetation: big bluestem, little bluestem, indiangrass, switchgrass, and other plants.
Ecological site: Claypan Upland (North) (R080AY010OK)

DISTRIBUTION AND EXTENT:
General area: Central Oklahoma
Land Resource Region: H, Central Great Plains Winter Wheat and Range Region
Major Land Resource Area: 80A- Central Rolling Red Prairies of Oklahoma and Texas
Extent: Moderate

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Pottawatomie County, Oklahoma; 1974

REMARKS: Seminole soils were formerly classified in the Reddish Prairie great soil group.

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 0 to 36 cm (0 to 14 in)(A horizon)
Natric horizon: 51 to 122 cm (20 to 48 in) (Btn horizons)
Argillic horizon: 51 to 122 cm (20 to 48 in) (Btn horizons)
Abrupt textural change: 51 cm (20 in) (top of Btn horizon)

ADDITIONAL DATA: Oklahoma State University laboratory data from
the series location plus other locations.

OSD pedon: P2019OK125001

TAXONOMIC VERSION: Keys to Soil Taxonomy, Twelfth Edition, 2014

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National Cooperative Soil Survey
U.S.A.