LOCATION WOODSON                 KS+MO OK

Established Series
Rev. DWS-ELF-RGC
12/2015

WOODSON SERIES

The Woodson series consists of very deep, somewhat poorly drained soils that formed in silty and clayey sediments. These soils are on interfluves, divides, and paleoterraces. Slope ranges from 0 to 3 percent. Mean annual precipitation is about 1092 mm (43 inches), and mean annual temperature is about 14 degrees C (57 degrees F).

TAXONOMIC CLASS: Fine, smectitic, thermic Abruptic Argiaquolls

TYPICAL PEDON: Woodson silt loam, in native grass on a nearly level summit of an interfluve, at an elevation of 324 meters (1063 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

A--0 to 20 cm (0 to 8 inches); very dark gray (10YR 3/1) silt loam, gray (10YR 5/1) dry; weak fine granular structure; slightly hard, friable; many roots throughout; moderately acid; abrupt smooth boundary. [18 to 36 cm (7 to 14 inches) thick]

Bt1--20 to 48 cm (8 to 19 inches); very dark gray (10YR 3/1) silty clay, dark gray (10YR 4/1) dry; moderate fine blocky structure; extremely hard, very firm; common roots throughout; few fine distinct dark brown (10YR 3/3) iron-manganese masses in the matrix; moderately acid; gradual smooth boundary.

Bt2--48 to 79 cm (19 to 31 inches); very dark gray (10YR 3/1) silty clay, gray (10YR 5/1) dry; moderate fine and medium blocky structure; extremely hard, very firm; many medium prominent strong brown (7.5YR 5/6) and few medium prominent olive brown (2.5Y 4/4) masses of oxidized iron in the matrix; fine and medium black (10YR 2/1) manganese concretions in the matrix; moderately acid; gradual smooth boundary. [Combined thickness of the Bt horizon is 41 to 89 cm (16 to 35 inches).]

BC--79 to 97 cm (31 to 38 inches); gray (10YR 5/1) silty clay, gray (10YR 6/1) dry; weak medium blocky structure; extremely hard, very firm; few roots throughout; common fine gypsum particles in the matrix; few medium prominent dark reddish brown (5YR 3/4) masses of oxidized iron in the matrix; few fine black (10YR 2/1) manganese concretions in the matrix; moderately acid; diffuse wavy boundary. [15 to 51 cm (6 to 20 inches) thick]

C--97 to 152 cm (38 to 60 inches); gray (10YR 5/1) silty clay, gray (10YR 6/1) dry; moderate fine and very fine blocky structure; extremely hard, very firm; very few roots throughout; common black (10YR 2/1) stains on vertical faces of peds; few fine gypsum particles in the matrix; many fine prominent olive (5Y 4/4) masses of oxidized iron in the matrix; common fine black (10YR 2/1) manganese concretions in the matrix; moderately acid.

TYPE LOCATION: Allen County, Kansas; 4 miles south of LaHarpe, Kansas; 100 feet south and 1,420 feet east of the northwest corner of sec. 23, T. 25 S., R. 19 E.; USGS Iola SE, Kansas topographic quadrangle; lat. 37 degrees 51 minutes 48 seconds N. and long. 95 degrees 17 minutes 8 seconds W.; UTM Zone 15, 298938 easting and 4193105 northing; NAD 83.

RANGE IN CHARACTERISTICS:
Thickness of the solum: 76 to 152 cm (30 to 60 inches)
Thickness of the mollic epipedon: 18 to 79 cm (7 to 31 inches)
Particle-size control section: averages 40 to 60 percent clay and 1 to 10 percent sand

A horizon:
Hue: 10YR
Value: 2 or 3, 3 to 5 dry
Chroma: 1
Texture: silt loam or silty clay loam
Clay content: 1 to 35 percent
Sand content: 1 to 20 percent
Reaction: moderately acid or slightly acid

Bt horizon (upper part):
Hue: 10YR or 2.5Y
Value: 2 or 3, 3 to 5 dry
Chroma: 1
Texture: silty clay or clay
Clay content: 40 to 55 percent
Sand content: 1 to 20 percent
Other feature: in some pedons the faces of peds are coated with grayish silt grains
Reaction: moderately acid to neutral

Bt horizon (lower part):
Hue: 10YR to 5Y
Value: 3 or 5, 4 to 6 dry
Chroma: 1
Texture: silty clay or clay
Clay content: 40 to 60 percent
Sand content: 1 to 20 percent
Reaction: moderately acid to neutral

C horizon:
Hue: 10YR to 5Y
Value: 4 to 6, 5 to 7 dry
Chroma: 1 to 3
Texture: silty clay loam, silty clay or clay
Clay content: 28 to 50 percent
Sand content: 1 to 20 percent
Reaction: moderately acid to slightly alkaline

COMPETING SERIES: There are no other series in this family.

GEOGRAPHIC SETTING: Woodson soils are on interfluves, divides, and paleoterraces on plains. Slope ranges from 0 to 3 percent. The soils formed in sediments that are high in silt and clay. The sediments are presumed to be old alluvium but may contain loess in the upper part and grade into residuum from shale in the lower part. Mean annual precipitation ranges from 889 to 1067 mm (35 to 42 inches). Mean annual temperature ranges from 14 to 18 degrees C (57 to 65 degrees F). Elevation is 215 to 405 meters (705 to 1330 feet) above mean sea level. Thornthwaite Annual P-E Index ranges from 64 to 78.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Aliceville, Bates, Dennis, Catoosa, Kenoma, Leanna, Lula, and Wagstaff soils. The better drained Bates, Dennis, and Kenoma soils are usually on more sloping topography. Aliceville, Catoosa, Lula, and Wagstaff soils are better drained and are commonly on nearby areas with similar slopes underlain by limestone. Leanna soils have albic horizons and are on flood plains and low terraces.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Depth to the top of a perched seasonal high water table ranges from 15 to 61 cm (6 to 24 inches) between November and June in normal years. Potential for surface runoff is high or very high. Saturated hydraulic conductivity is low. Permeability is very slow.

USE AND VEGETATION: Mostly areas are used as cropland. Soybeans, grain sorghums, wheat, corn, and alfalfa are the principal crops. Some areas are used as grassland. Native vegetation is dominated by tall grass species.

DISTRIBUTION AND EXTENT: MLRAs 112, 116, and 118 in southeast Kansas, southwestern Missouri and northeastern Oklahoma. The type location is in MLRA 112. The series is extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana.

SERIES ESTABLISHED: Neosho County, Kansas, l930.

REMARKS: Diagnostic horizons and features recognized in this pedon are: Mollic epipedon: from the surface to a depth of 79 cm (31 inches) (A, Bt horizon).
Argillic horizon: from a depth of 20 to 79 cm (8 to 31 inches) (Bt horizon).
Aquic conditions: redox features present in all horizons below a depth of 20 cm (8 inches).

The Woodson series was formerly classified in the mixed mineralogy class.

12/2015 revision: updated landforms based on review of NASIS data; updated terminology used to describe redox features; added geographic coordinates; sand and clay content ranges; also added Aliceville to list of geographically associated soils; added MLRAs 116 and 118 to extent.

ADDITIONAL DATA: Lab data is available for several pedons at the Kellogg Soil Survey Laboratory, Lincoln, NE.

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National Cooperative Soil Survey
U.S.A.