LOCATION NEPESTA COEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Ustic Haplargids
TYPICAL PEDON: Nepesta clay loam - cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 38 centimeters (0 to 15 inches); grayish brown (10YR 5/2) clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure that parts to fine granules; slightly hard, very friable, slightly sticky, slightly plastic; primary peds are hard, firm; moderate amounts of partially decomposed organic plant remains; calcareous; moderately alkaline (pH 8.0); abrupt smooth boundary. (25 to 51 centimeters (10 to 20 inches) thick)
B2t--38 to 64 centimeters (15 to 25 inches); light brownish gray (10YR 6/2) silty clay loam, dark grayish brown (10YR 4/2) moist; moderate medium prismatic structure that parts to moderate and fine subangular blocks; slightly hard, friable, slightly sticky, slightly plastic; peds are very hard, firm; thin nearly continuous wax-like coatings on faces of peds and wax-like coatings and fillings on the inside of root channels and pores; calcareous; moderately alkaline (pH 8.0); gradual wavy boundary. (13 to 66 centimeters (5 to 26 inches) thick)
B3ca--64 to 76 centimeters (25 to 30 inches); light yellowish brown (2.5Y 6/3) light silty clay loam, light olive brown (2.5Y 5/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic; peds are very hard, firm; glossy patches on the faces of some peds and discontinuous glossy coatings on the inside of root channels and pores; visible secondary calcium carbonate occurring as concretions and in thin seams and streaks; calcareous; moderately alkaline (pH 8.2); gradual wavy boundary. (8 to 15 centimeters (3 to 6 inches) thick)
Cca--76 to 137 centimeters (30 to 54 inches); light gray (2.5Y 7/2) light silty clay loam, light olive brown (2.5Y 5/3) moist; massive; hard, friable, slightly sticky, slightly plastic; visible secondary calcium carbonate occurring as concretions and in thin seams and streaks; calcareous; moderately alkaline (pH 8.4).
TYPE LOCATION: Prowers County, Colorado; approximately 0.72 kilometers (.45 mile) east and 0.24 kilometer (.15 mile) north of SW corner Sec. 19, T. 21 S., R. 47 W.
RANGE IN CHARACTERISTICS:
Calcareous: throughout except that thin discontinuous noncalcareous subhorizons occur in the B2t horizon in some pedons.
Depth of the argillic horizon: 38 to 102 centimeters (15 to 40 inches)
Depth to continuous subhorizons of visible secondary carbonate and/or sulfate: 30 to 102 centimeters (12 to 40 inches), such horizons not strong enough to qualify as calcic or gypsic horizons
ESP: remains constant or increases with depth, ranges from 0 to 15 percent in the solum but exceeds 15 percent in the Cca horizon
Conductivity: 0 to 14 millimhos in all subhorizons that are at least 3 inches thick above a depth of 51 centimeters (20 inches)
Subhorizons color: hues of 7.5YR or yellower in control section above 102 centimeters (40 inches), redder than 7.5YR occur in some pedons
Rock fragments: 0 to 5 percent by volume in the solum and in the C horizon above a depth of 102 centimeters (40 inches)
Man-made Ap horizons: 25 to 51 centimeters (10 to 20 inches) thick, medium to moderately fine textured, border mollic epipedons in color and anthropic epipedons in amounts of phosphorous and nitrogen characterize these soils
They have resulted from long periods of irrigation with silt laden irrigation water accompanied by intense cropping, heavy fertilization, and larger than normal yearly returns of organic matter.
Ap horizon:
Hue: 2.5Y to 7.5YR
Value: 5 to 7, 3 to 6 moist
Chroma: 1 to 4
Reaction: moderately or strongly alkaline (1:5 dilution unbuffered organic dye)
B2t horizon:
Hue: 2.5Y to 7.5YR (Subhorizons redder than 7.5YR occur in some pedons)
Value: 5 to 7, 4 to 6 moist
Chroma: 1 to 6
Texture: silt loam, loam, clay loam, or silty clay loam
Clay content: 10 to 35 percent
Silt content: 20 to 70 percent
Sand content: 10 to 60 percent, less than 35 percent being fine or coarser sand
Reaction: moderately or strongly alkaline.
COMPETING SERIES: These are the Blanding, Buick, Del Rio, Fernando, Keiser, Pulpit, Roubideau, Sharps, Tensleep, Verde, Wiley, and Witt series. Blanding, Buick, Del Rio, Fernando, Keiser, Tensleep, Wiley, and Witt soils lack a thick man-made Ap horizon. Also, Blanding and Tensleep soils have hue of 5YR or redder in a majority of subhorizons above a depth of 40 inches. Buick, Del Rio, and Witt soils have solums more than 40 inches thick and Keiser soils have solums less than 15 inches to the base of the argillic horizon. Pulpit, Roubideau, Sharps, and Verde soils have bedrock at depth of 20 to 40 inches
GEOGRAPHIC SETTING:
Landscape: terraces and alluvial fans
Slopes: 0 to 6 percent or more
Parent material: calcareous eolian or alluvial materials usually containing a large amount of very fine sand
Mean annual precipitation: 38 centimeters (15 inches), peak periods of precipitation in the spring and early summer months
Mean annual temperature is 11 degrees C. (52 degrees F.)
Mean summer temperature is 26 degrees C. (79 degrees F.)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Neesopah and Rocky Ford soils. Neesopah soils are moderately coarse textured. Rocky Ford soils lack an argillic horizon
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Runoff: low to very low
Saturated hydraulic conductivity: moderately high
USE AND VEGETATION: Used as irrigated cropland.
Major irrigated crops are alfalfa, small grains, corn, sorghum, truck crops, and melons.
DISTRIBUTION AND EXTENT: Arkansas River Valley, Colorado. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Salina, Kansas
SERIES ESTABLISHED: Prowers County, Colorado, 1963
REMARKS: Last updated by the state 4/73.
Modified format by LRM and JCR in 10/2005 to include metric conversion and change permeability to saturated hydraulic conductivity.