LOCATION DUKE                    OK+TX

Established Series
RFG-WJG-ROG
09/2020

DUKE SERIES

The Duke series consists of very deep, well drained, very slowly permeable soils that formed in clayey alluvium derived from Permian age redbed sediments. These nearly level soils are on flood plains. Slope ranges from 0 to 1 percent. Mean annual precipitation is about 61 cm (24 in) and the mean annual temperature is about 16 degrees C (61 degrees F)

TAXONOMIC CLASS: Fine, mixed, active, thermic Sodic Haplusterts

TYPICAL PEDON: Duke silty clay in pastureland (Colors are for dry soil unless otherwise stated.)

Ap--0 to 13 cm (0 to 5 in); reddish brown (5YR 4/3) silty clay, dark reddish brown (5YR 3/3), moist; moderate medium granular structure; friable, hard; common fine and medium roots; common fine and medium pores; very slight effervescence; moderately alkaline (pH 7.9); abrupt smooth boundary. (Thickness is 10 to 30 cm [4 to 12 in])

Bnyz1--13 to 28 cm (5 to 11 in); reddish brown (5YR 5/3) clay, reddish brown (5YR 4/3), moist; weak coarse prismatic structure parting to moderate medium angular blocky structure; firm, hard; common fine and medium roots; few fine and medium pores; 20 percent distinct pressure faces; 2 percent fine salt masses along root channels; 1 percent fine gypsum masses along root channels; slight effervescence; slightly alkaline (pH 7.8); gradual smooth boundary. (Thickness is 0 to 51 cm [0 to 20 in])

Bssnyz2--28 to 63 cm (11 to 25 in); reddish brown (5YR 5/4) clay, reddish brown (5YR 4/4), moist; weak coarse prismatic structure parting to moderate medium angular blocky structure; very firm, very hard; common fine and very fine roots; few fine and common very fine pores; 10 percent distinct slickensides; 30 percent distinct pressure faces; 3 percent fine salt masses along root channels; 2 percent fine gypsum masses along root channels; 1 percent fine carbonate masses; strong effervescence; slightly alkaline (pH 7.7); gradual smooth boundary. (Combine thickness is 38 to 190 cm [15 to 75 in])

Bnyz3--63 to 86 cm (25 to 34 in); reddish brown (5YR 5/4) silty clay, reddish brown (5YR 4/4), moist; moderate coarse prismatic structure parting to moderate medium subangular blocky structure; firm, very hard; common fine and very fine roots; few fine and common very fine pores; 1 percent fine salt masses along root channels; 1 percent fine gypsum masses along root channels; strong effervescence; slightly alkaline (pH 7.7); clear smooth boundary.

Bnyz4--86 to 112 cm (34 to 44 in); yellowish red (5YR 5/6) silty clay loam, yellowish red (5YR 4/6), moist; weak coarse prismatic structure parting to moderate medium subangular blocky structure; firm, very hard; few very fine roots; few fine and common very fine pores; 1 percent fine salt masses along root channels; strong effervescence; slightly alkaline (pH 7.6); clear wavy boundary. (Combined thickness is 76 to 190 cm [30 to 75 in])

BC1--112 to 165 cm (44 to 65 in); 50 percent yellowish red (5YR 5/6) and 30 percent reddish brown (5YR 4/3) and 20 percent light brown (7.5YR 6/4) stratified with many 0.63 cm (1/4 in) to 2.54cm (1 in) thick strata of loam and silt loam, 50 percent yellowish red (5YR 4/6) and 30 percent dark reddish brown (5YR 3/3) and 20 percent brown (7.5YR 5/4), moist; weak very coarse prismatic structure parting to weak medium platy structure; very friable, hard; few very fine roots; common fine and common medium pores; strong effervescence; slightly alkaline (pH 7.7); clear smooth boundary. (Combine thickness is 0 to 127 cm [0 to 50 in])

BC2--165 to 221 cm (65 to 87 in); 70 percent reddish brown (5YR 4/3) and 20 percent reddish brown (5YR 5/4) and 10 percent light brown (7.5YR 6/4) stratified with three 3 inch thick strata separated by many 0.32 cm (1/8 in) to 1.27 cm (1/2 in) thick strata of silt loam and loam, 70 percent dark reddish brown (5YR 3/3) and 20 percent reddish brown (5YR 4/4) and 10 percent brown (7.5YR 5/4), moist; weak very coarse prismatic structure parting to weak medium platy structure; very friable, hard; few very fine roots; common fine and medium pores; slight effervescence; slightly alkaline (pH 7.7).

TYPE LOCATION: Harmon County, Oklahoma; From the intersection of U.S. Highway 62 and OK State Highway 30 in Hollis, 12 miles east on highway 62 to McQueen, then north 2.36 miles on a county road, then 548 meter (1800 feet) east in pasture; 579 meter (1900 feet) north and 548 meter (1800 feet) east of the southwest corner of Section 26, T. 3 N., R. 24 W.; USGS topographic quadrangle: McQueen, OK; Latitude: 34 degrees 42 minutes 4.54 seconds N; Longitude: 99 degrees, 41 minutes 47.20 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Typic-ustic soil moisture regime
Mean annual soil temperature: 17 degrees C (63 degree F)

Particle-size control section (weighted average)
Clay content: 35 to 60 percent
Sand content: 0 to 45 percent
Rock fragments: 0 to 2 percent gravel
Depth to visible calcium carbonate: 0 to 20 inches
Depth to salt accumulations: 0 to 101 cm (0 to 40 in)
Depth to SAR of 13 or more, or ESP of 15 or more: 13 to 76 cm (5 to 30 in)
Depth to vertic features: 13 to 76 cm (5 to 30 in)
Some pedons contain buried horizons below 76 cm (30 in)

A Horizon:
Hue: 2.5YR to 7.5YR
Value: 4 to 6 (3 to 5 moist)
Chroma: 2 to 6
Texture: clay, silty clay, silty clay loam, or clay loam
Total clay content: 28 to 60 percent
Gypsum: 0 to 1 percent
Electrical Conductivity (dS/m): 0 to 4
Sodium Adsorption Ratio: 0 to 4
Calcium carbonate equivalent (CCE): 0 to 15 percent
Effervescence: None to strong
Reaction: Slightly or moderately alkaline (pH 7.4 - 8.4)

Upper part of the B Horizon:
Hue: 2.5YR or 5YR
Value: 4 to 6 (3 to 5 moist)
Chroma: 3 to 6
Texture: silty clay loam, clay loam, silty clay or clay
Total clay content: 35 to 65 percent
Identifiable secondary carbonate: none to common masses, threads, and concretions
Identifiable salts: none to few masses or crystals
Gypsum: 0 to 5 percent
Electrical conductivity (dS/m): 0 to 8
Sodium Adsorption Ratio: 1 to 15
Calcium carbonate equivalent (CCE): 1 to 15 percent
Effervescence: slight to violent
Reaction: Slightly or moderately alkaline (pH 7.4 - 8.4)

Lower part of the B Horizon:
Hue: 2.5YR or 5YR
Value: 4 to 6 (3 to 5 moist)
Chroma: 3 to 6
Texture: silty clay loam, clay loam, silty clay or clay
Clay content: 35 to 65 percent
Identifiable secondary carbonate: none to common masses, threads, and concretions
Gypsum: 0 to 15 percent
Electrical Conductivity (dS/m): 2 to 16
Sodium adsorption ratio: 4 to 20
Calcium carbonate equivalent (CCE): 1 to 15 percent
Effervescence: slight to violent
Reaction: Slightly or moderately alkaline (pH 7.4 - 8.4)

BC or C Horizon:
Hue: 2.5YR or 5YR
Value: 4 to 6 (3 to 5 moist)
Chroma: 3 to 6
Texture: loam to clay and may be stratified
Total clay content: 15 to 60 percent
Identifiable secondary carbonate: none to common masses, threads, and concretions
Identifiable salts: few to common masses or crystals
Gypsum: 2 to 15 percent
Electrical conductivity (dS/m): 2 to 16
Sodium Adsorption Ratio: 4 to 20
Calcium carbonate equivalent (CCE): 1 to 15 percent
Effervescence: slight to violent
Reaction: Slightly or moderately alkaline (pH 7.4 - 8.4)

COMPETING SERIES: There are no series in the same family. Similar soils are the Kingco, Lela, Mangum, Padgett, and Throck series.
None of these series have an exchangeable sodium percentage of 15 or more within 101 cm (40 in) of the surface.
Kingco and Throck series: These soils occur on higher landscape positions and do not flood.
Lela series: These soils have a mollic epipedon and occur in a wetter climate.
Mangum series: These soils do not have electrical conductivity more than 2 dS/m within 101 (40 in) of the surface.
Padgett series: These soils occur in a slightly wetter climate and gilgai microrelief are common in undisturbed areas.

GEOGRAPHIC SETTING:
Parent material: recent calcareous clayey alluvium derived from Permian age redbed sediments
Landscape: dissected plains
Landform: flood plains
Slope: 0 to 1 percent
Mean annual precipitation range: 558 to 711 mm (22 to 28 in)
Thornthwaite P-E indices: 32 to 44
Mean annual air temperature range: 15 to 17 degrees C (59 to 64 degrees F)
Frost-free period: 200 to 230 days
Elevation: 305 to 609 m (1000 to 2000 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beckman, Clairemont, Gageby, Hayfork, Knoco, Spur, Tillman, Tilvern, Treadway, Vernon, Westill, and Wheatwood series.
Beckman series: These soils occur on slightly lower flood plains, are moderately well drained, and do not have vertic properties.
Clairmont, Gageby, Spur, and Wheatwood series: These soils occur on similar positions, but have less than 35 percent clay in the particle-size control section.
Hayfork series: These soils occur on slightly higher flood plains and have a mollic epipedon.
Knoco, Tilvern, and Vernon series: These soils occur on surrounding upland slopes and have Permian age redbed sediments within 152 cm (60 in).
Tillman and Westill series: These soils occur on surrounding upland slopes and have mollic epipedons and argillic horizons.
Treadway series: These soils occur on higher foot slopes and alluvial fans and do not have vertic properties.

DRAINAGE AND PERMEABILITY:
Drainage class: well
Permeability: very slow
Runoff: high
Flooding: frequently or occasionally flooded for very brief periods during the months April to October.

USE AND VEGETATION:
Major uses: livestock grazing, but a few areas are cultivated to wheat and grain sorghum.
Native vegetation: buffalograss, sideoats grama, vine mesquite, and western wheatgrass. Mesquite brush is the prevalent invader. Ecological sites assigned to phases and components of this series are listed below. Current ecological site assignments are in Web Soil Survey. Components of this series include the following ecological sites: Clayey Bottomland

DISTRIBUTION AND EXTENT:
General location: Central Rolling Red Plains of southwestern Oklahoma and northwestern Texas; MLRA 78B and 78C; Extent: small

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

SERIES PROPOSED: Greer County, Oklahoma; 2004.

REMARKS: Edited 08/2020 (LL-ROG): Converted to tabular format and added metric measurements.

Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 25 to 101 cm (10 to 40 in)
Ochric epipedon: 0 to 13 cm (0 to 5 in) (Ap horizon)
Vertic features: The presence of pressure faces and slickensides at 13 to 63 cm (5 to 25 in). (Byz1 and Bssyz2 horizons)
Sodic features: An exchangeable sodium percentage of more than 15 percent from 12 to 221 cm (5 to 87 in)
Additional Comments:
These soils were included in the Mangum series in some earlier soil surveys.
These soils have open cracks during dry periods.
The assignment of the cation-exchange activity class is supported by laboratory data number S03OK-057-006 from Harmon County, OK and S00OK-055-004 from Greer County, OK.
Range Site: Clayey Bottomland PE 25-36 (078BY070TX)
Clayey Bottomland PE 31-44 (078CY094TX)

ADDITIONAL DATA: NSSL data: S03OK-057-006 from Harmon County, OK and S00OK-055-004 from Greer County, OK

Taxonomic Version: Soil Taxonomy, Twelfth Edition, 2014

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National Cooperative Soil Survey
U.S.A.