LOCATION SPEARVILLE KSEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Typic Argiustolls
TYPICAL PEDON: Spearville silty clay loam - cultivated. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 18 centimeters (0 to 7 inches); dark grayish brown (10YR 4/2) silty clay loam, very dark brown (10YR 2/2) moist; moderate medium granular structure; hard, friable; neutral; clear smooth boundary. (10 to 25 centimeters (4 to 10 inches) thick)
Bt1--18 to 30 centimeters (7 to 12 inches); dark grayish brown (10YR 4/2) silty clay, very dark brown (10YR 2/2) moist; moderate fine and very fine blocky structure; very hard, very firm; few pores; neutral; gradual smooth boundary. (3 to 10 inches thick)
Bt2--30 to 51 centimeters (12 to 20 inches); grayish brown (10YR 5/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate coarse blocky structure; very hard, very firm; moderately alkaline; gradual smooth boundary. (3 to 10 inches thick)
Bk1--51 to 66 centimeters (20 to 26 inches); light brownish gray (10YR 6/2) heavy silty clay loam, brown (10YR 5/3) moist; moderate coarse blocky structure; hard, friable; common fine soft bodies of calcium carbonate; strong effervescence; moderately alkaline; gradual smooth boundary. (10 to 30 centimeters (4 to 12 inches) thick)
Bk2--66 to 102 centimeters (26 to 40 inches); pale brown (10YR 6/3) silty clay loam, brown (10YR 5/3) moist; weak coarse subangular blocky structure; slightly hard, friable; few soft bodies of calcium carbonate; strong effervescence; moderately alkaline; diffuse smooth boundary. (0 to 25 centimeters (0 to 10 inches) thick)
C--102 to 152 centimeters (40 to 60 inches); pale brown (10YR 6/3) heavy silt loam, brown (10YR 5/3) moist; weak coarse prismatic structure; slightly hard, friable; fine threads and coatings of calcium carbonate on faces of peds; strong effervescence; moderately alkaline
TYPE LOCATION: Ford County, Kansas; about 13 kilometers (8 miles) north and 8 kilometers (5 1/4 miles) west of Dodge City, Kansas; 140 meters (460 feet) south and 18 meters (60 feet) west of the northeast corner of sec. 19, T. 25 S., R 25 W.
RANGE IN CHARACTERISTICS:
The thickness of the solum ranges from 51 to 114 centimeters (20 to 45 inches)
Depth to free carbonates: 25 to 64 centimeters (10 to 25 inches)
Mollic epipedon: 25 to 51 centimeters (10 to 20 inches) thick
A horizon:
Hue: 10YR
Value: 3 to 5, 2 or 3 moist
Chroma: 2 or 3
Texture: silty clay loam and less commonly silt loam
Reaction: neutral to moderately alkaline
A and Bt horizons boundary: clear or abrupt
Bt1 horizon
Colors like the A horizon
Reaction: neutral to moderately alkaline
Clay content: 42 to 50 percent
Bt2 horizon:
Hue: 10YR
Value: 4 or 5, 3 or 4 moist
Chroma: 2 or 3
Reaction: neutral to moderately alkaline
Bk horizon:
Hue: 10YR
Value: 5 or 6, 4 or 5 moist
Chroma: 2 or 3
Texture: silty clay or silty clay loam
Secondary carbonates: soft rounded masses and films
C horizon:
Hue: 10YR or 2.5Y
Value: 6 or 7, 5 or 6 moist
Chroma: 2 or 3
Horizon: usually calcareous loess, (pedons where the loess layer is thin, contrasting material is below depths of 102 centimeters (40 inches)
COMPETING SERIES: These are the
Beadle,
Brolliar,
Carlson,
Harney,
McClure,
Mento,
Raber and
Reliance series
Beadle and Raber soils contain more sand and are formed in glacial till.
Brolliar soils have basalt bedrock at 51 to 102 centimeters (20 to 40 inches)
Carlson soils are formed in material weathered from calcareous residuum and have argillic horizons averaging less than 45 percent clay.
Harney soils average less than 42 percent clay in the control section and have a gradual boundary between the A and Bt horizons.
McClure and Reliance soils have mean annual temperatures less than 52 degrees F.
Mento soils have bedrock at depths of 102 to 178 centimeters (40 to 70 inches) and Bt horizons which average 35 to 45 percent clay.
GEOGRAPHIC SETTING:
Landform: loess covered uplands having slightly concave to convex surfaces
Slope: 0 to 3 percent
Parent material: loess
Mean annual precipitation: 46 to 61 centimeters (18 to 24 inches)
Thornthwaite Annual P-E Index: 30 to 36
Mean annual temperature: 11 to 14 degrees C. (52 to 57 degrees F.)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Ness and
Uly soils.
The more clayey Ness soils are in depressions.
Uly soils lack argillic horizons.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained and moderately well drained
Runoff: low and very low
Saturated Hydraulic Conductivity: moderately low
USE AND VEGETATION: Most of the Spearville soils are cultivated.
The main dryland crops are wheat and sorghums.
When irrigated the major crops are wheat, grain sorghum, corn, and alfalfa.
Native vegetation is short and mid grasses.
DISTRIBUTION AND EXTENT: Western Kansas and the Oklahoma Panhandle. The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Ford County, Kansas, 1962.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 0 to 51 centimeters (0 to 20 inches) (A, Bt1, Bt2)
Argillic horizon: 18 to 51 centimeters (7 to 20 inches) (Bt1, Bt2)
ADDITIONAL DATA: Laboratory data is available from the Lincoln, Nebraska soils laboratory on Pedons S63Kans-29-1 and S63Kans-29-2. Laboratory Nos. 18450-18462 and 18463-18470 respectively
Modified format by LRM in 3/2006 to include metric conversion and change permeability to saturated hydraulic conductivity.