LOCATION EASPUR                  OK

Established Series
JEH Rev.:CS:JLD
02/2016

EASPUR SERIES

The Easpur series consists of very deep, well drained soils that formed in loamy alluvium of Holocene age. These soils are on flood plains of small streams in the Central Rolling Red Prairies (MLRA 80A). Slope ranges from 0 to 1 percent. Mean annual temperature is 16.1 degrees (61 degrees F), and mean annual precipitation is 914 mm (36 in).

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Fluventic Haplustolls

TYPICAL PEDON: Easpur loam-cultivated, at an elevation of 259 m (850 ft). (Colors are for dry soil unless otherwise stated.)

Ap--0 to 28 cm (0 to 11 in); reddish brown (5YR 4/3) loam, dark reddish brown (5YR 3/3) moist; weak fine granular structure; slightly hard, friable; many fine roots; slightly acid; clear smooth boundary. (Thickness of the A horizon is 20 to 36 cm [8 to 14 in])

Bw1--28 to 48 cm (11 to 19 in); reddish brown (5YR 5/4) fine sandy loam, reddish brown (5YR 4/4) moist; weak fine granular structure; soft, very friable; many fine roots; neutral; clear smooth boundary.

Bw2--48 to 74 cm (19 to 29 in); reddish brown (5YR 4/4) clay loam, dark reddish brown (5YR 3/4) moist; moderate fine granular structure; hard, firm; few fine roots; neutral; clear smooth boundary. (Combined thickness of the Bw horizon 15 to 122 cm [6 to 48 in])

C--74 to 104 cm (29 to 41 in); stratified reddish brown (5YR 5/4) loam, yellowish red (5YR 5/6) fine sandy loam, and reddish brown (5YR 4/3) clay loam; massive; slightly hard, friable; few fine roots; strata are 2.5 to 5 cm (1 to 4 in) thick; noneffervescent; slightly alkaline; clear smooth boundary. (Thickness of the C horizon is 0 to 84 cm [0 to 33 in])

2Ab--104 to 157 cm (41 to 62 in); dark reddish gray (5YR 4/2) silty clay loam, dark reddish brown (5YR 3/2) moist; moderate fine granular structure; hard, firm; noneffervescent; slightly alkaline; clear smooth boundary. (Thickness of the Ab horizon is 25 to 53 cm [10 to 21 in])

2Bwb--157 to 183 cm (62 to 72 in); reddish brown (5YR 4/4) silty clay loam, dark reddish brown (5YR 3/4) moist; weak medium subangular blocky structure; hard, firm; noneffervescent; slightly alkaline.

TYPE LOCATION: Payne County, Oklahoma; about 0.5 mile west of Stillwater, Oklahoma; 2,000 feet east and 1,300 feet north of the southwest corner of sec. 16, T. 19 N., R. 2 E.

USGS topographic quadrangle: Stillwater South, OK
Latitude 36 degrees, 7 minutes, 10 seconds N
Longitude 97 degrees, 5 minutes, 54 seconds W
Datum: NAD 83

UTM Easting: 671131 m
UTM Northing: 3998900 m
UTM Zone 14N

RANGE IN CHARACTERISTICS:
Solum thickness: 51 to more than 152 cm (20 to more than 60 in) and commonly is the same as depth to buried horizons
Depth to secondary carbonates: below 127 cm (50 in)

Ap or A horizon:
Hue: 5YR or 7.5YR
Value: 4 or 5, moist 3
Chroma: 2 or 3
Texture: loam or silt loam
Effervescence: none
Reaction: moderately acid to moderately alkaline

Bw horizon:
Hue: 2.5YR to 7.5YR
Value: 4 to 6, moist 3 or 4
Chroma: 3 to 6
Texture: fine sandy loam, very fine sandy loam, loam, or clay loam
Effervescence: none
Reaction: slightly acid to moderately alkaline

C horizon:
Hue: 2.5YR to 10YR
Value: 4 to 7, moist 3 to 5
Chroma: 3 to 6
Texture: stratified with thin layers of fine sandy loam to clay loam
Effervescence: none
Reaction: slightly acid to moderately alkaline

2Ab horizon:
Hue: 5YR or 7.5YR
Value: 3 to 5, moist 3 or 4
Chroma: 2 or 3
Texture: silt loam, loam, silty clay loam, or clay loam
Effervescence: none
Reaction: slightly acid to moderately alkaline

2Bwb horizon:
Hue: 5YR to 10YR
Value: 4 or 5, moist 3 or 4
Chroma: 2 to 4
Texture: silt loam, loam, silty clay loam, or clay loam
Effervescence: none
Reaction: slightly acid to moderately alkaline

COMPETING SERIES: These are the Pursley and Spur series in the same family. Soils in similar families in MLRA 80A are Asher, Ashport, Keokuk, and Pocasset series.
Asher soils: have a fine-silty control section and have secondary carbonates within 102 cm (40 in)
Ashport soils: have a fine-silty control section
Keokuk soils: have a coarse-silty control section
Pocasset soils: have a coarse-loamy control section
Pursley soils: are in a warmer climate, and have subsoil hues of 10YR or yellower
Spur soils: are dry for longer periods and have secondary carbonates within 102 cm (40 in)

GEOGRAPHIC SETTING:
Parent material: formed in loamy alluvium of Holocene age
Landscape: alluvial plain
Landform: flood plains of small streams in the Central Rolling Red Prairies
Slope: 0 to 1 percent
Mean Annual Precipitation: 838 to 991 mm (33 to 39 in)
Mean Annual Temperature: 15 to 17.2 degrees C (59 to 63 degrees F)
Frost-free period: 181 to 240 days
Elevation: 229 to 305 m (750 to 1000 ft)
Thornthwaite Annual P-E indices: 44 to 64

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Port, Dale, and Pulaski series.
Dale soils: are on slightly higher positions, are rarely flooded, and have a mollic epipedon more than 50 cm (20 in) thick and have a fine-silty control section
Port soils: are on similar positions, have a mollic epipedon more than 50 cm (20 in) thick, and have a fine-silty control section
Pulaski soils: are typically closer to the stream channel, have a coarse-loamy control section, and do not have a mollic epipedon

DRAINAGE AND PERMEABILITY:
Drainage: Well drained
Permeability: moderate
Saturated hydraulic conductivity: Moderately high
Runoff: Negligible
Flooding: Occasionally flooded for very brief to brief periods during March to October

USE AND VEGETATION: These soils are mainly cultivated. Alfalfa, small grains, and grain sorghum are the principal crops. Some areas are used for improved pasture or rangeland. Native vegetation is tall grasses with an overstory of pecan, black walnut, bur oak, and Eastern cottonwood trees.

DISTRIBUTION AND EXTENT: Central Oklahoma; LRR H; Central Rolling Red Prairies (MLRA 80A); these soils are not extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Payne County, Oklahoma; 1983 by J.E. Henley

REMARKS:

These soils were formerly included in the Port series

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 0 to 28 cm (0 to 11 in) (A horizon)
Cambic horizon: 28 to 74 cm (11 to 19 in) (Bw horizon)
Lithologic discontinuity: contrasting materials at a depth of 74 cm (41 in)

ADDITIONAL DATA: Sample 79-OK-60-16 was done by Oklahoma State University.

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014

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National Cooperative Soil Survey
U.S.A.