LOCATION SULCO NEEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, calcareous, mesic Aridic Ustorthents
TYPICAL PEDON: Sulco loam on convex east-facing slope of 14 percent under native grass. (Colors are for dry soil unless otherwise stated.) When described the soil was dry throughout.
A--0 to 8 centimeters (0 to 3 inches); grayish brown (10YR 5/2) loam, dark grayish brown (10YR 4/2) moist; weak medium granular structure; slightly hard, friable; slightly alkaline; clear smooth boundary.
Bw--8 to 15 centimeters (3 to 6 inches); brown (10YR 5/3) loam, brown (10YR 4/3) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; slightly hard, friable; strongly effervescent; 3 percent calcium carbonate equivalent; moderately alkaline; clear smooth boundary. (Combined thickness of the A and Bw horizons is less than 25 centimeters (10 inches) thick).
Bk1--15 to 41 centimeters (6 to 16 inches); pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; slightly hard, friable; many fine and medium soft accumulations of carbonate; violently effervescent; 13 percent calcium carbonate equivalent; moderately alkaline; diffuse wavy boundary.
Bk2--41 to 69 centimeters (16 to 27 inches); pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; slightly hard, friable; many fine and medium soft accumulations of carbonate; violently effervescent; 12 percent calcium carbonate equivalent; strongly alkaline; clear smooth boundary. (The thickness of the Bk horizons range from 0 to 61 centimeters (0 to 24 inches) thick.
C1--69 to 102 centimeters (27 to 40 inches); pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; massive; soft, very friable; strongly effervescent; 8 percent calcium carbonate equivalent; strongly alkaline; diffuse wavy boundary.
C2--102 to 127 centimeters (40 to 50 inches); light yellowish brown (10YR 6/4) loam, yellowish brown (10YR 5/4) moist; massive; soft, very friable; strongly effervescent; 7 percent calcium carbonate equivalent; strongly alkaline; diffuse wavy boundary.
C3--127 to 203 centimeters (50 to 80 inches); very pale brown (10YR 7/3) loam, pale brown (10YR 6/3) moist; massive; soft, very friable; strongly effervescent; 6 percent calcium carbonate equivalent; strongly alkaline.
TYPE LOCATION: Dundy County, Nebraska; about 24 kilometers (15 miles) north of Benkelman; 549 meters (1800 feet) east and 152 meters (500 feet) north of the southwest corner of sec. 29, T. 4 N., R. 37 W. USGS Ough topographic quadrangle; latitude 40 degrees, 18 minutes, 55 seconds North and longitude 101 degrees, 34 minutes, 16 seconds West.
RANGE IN CHARACTERISTICS:
Particle size distribution:
Clay content: 8 to 17 percent
Silt content: 30 to 55 percent
Sand content: 30 to 60 percent, 85 percent or more of the total sand consists of very fine sand
Particle size distribution is relatively uniform throughout
Depth to carbonates: 0 to 15 centimeters (0 to 6 inches)
Carbonate equivalent series control section: 5 to 15 percent, most occur as accumulations
Comments: These soils typically have a Bw horizon that is too thin to qualify for a cambic horizon.
A horizon:
Hue: 10YR
Value: 4 to 6, 3 to 5 moist
Chroma: 2 to 3
Reaction: slightly or moderately alkaline
Texture: silt loam, loam, very fine sandy loam, fine sandy loam
Bw horizon:
Hue: 10YR, 2.5Y
Value: 5 to 7, 4 to 6 moist
Chroma: 2 to 3
Reaction: slightly or moderately alkaline
Texture: silt loam, loam, very fine sandy loam
Comments: Some pedons have an AC horizon that ranges up to 38 centimeters (15 inches) thick. In cultivated areas, some pedons do not have an AC or Bw horizon.
Bk horizons (if they occur):
Hue: 10YR, 2.5Y
Value: 5 to 7, 4 to 6 moist
Chroma: 2 to 3
Accumulations of carbonates: few to common
Reaction: moderately or strongly alkaline
Texture: silt loam, loam, very fine sandy loam
C horizons:
Hue: 10YR, 2.5Y
Value: 5 to 7, 4 to 6 moist
Chroma: 2 to 4
Reaction: moderately or strongly alkaline
Texture: silt loam, loam, very fine sandy loam
COMPETING SERIES: These are the Benkelman and Nevee series.
Benkelman soils formed in alluvial sediments on stream terraces and alluvial fans, particle size distribution is irregular throughout the series control section, calcium carbonates do not occur as accumulations, carbonate equivalent is less than 5 percent
Nevee soils have a depth to bedrock from 102 to 152 centimeters (40 to 60 inches) or more, formed in silty alluvium weathered from reddish colored silty shale, siltstone or sandstone
GEOGRAPHIC SETTING:
Landscape: tablelands, uplands
Landform: hillslopes, drainageways
Slopes: 3 to 60 percent
Elevation: 914 to 1524 centimeters (3000 to 5000 feet)
Parent material: calcareous silty loess
Mean annual air temperature: 8 to 12 degrees C. (47 to 54 degrees F.)
Mean annual precipitation: 36 to 46 (14 to 18 inches)
Frost-free period: 130 to 160 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are
Kanorado,
McConaughy and
Ulysses series.
Kanorado soils have shale at 102 to 152 centimeters (40 to 60 inches) and fine textured.
McConaughy soils have a mollic epipedon and are lower on the landscape.
Ulysses soils have a mollic epipedon and are fine-silty.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Runoff: low to very high
Saturated Hydraulic Conductivity: moderately high.
USE AND VEGETATION: Used mostly for rangeland and a few areas are used for cropland.
Small grain, corn and sorghum are the main crops grown.
Native grasses are dominantly blue grama, little bluestem, sideoats grama, threadleaf sedge, western wheatgrass, big bluestem and forbs.
DISTRIBUTION AND EXTENT: Southwest Nebraska and northwest Kansas. It is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Garden County, Nebraska, 1994.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 8 centimeters (0 to 3 inches) (A horizon)
Moisture regime: aridic-ustic
A fine sandy loam surface was added (4/00) because a map unit with this surface texture has been correlated in the Dundy County update. These soils were previously mapped with the Colby series because they were thought to be fine-silty.
ADDITIONAL DATA: National Soil Survey Laboratory Data available for pedons S88NE-057-007, S88NE-057-001 and S90NE-057-021.
OTHER DATA:
T:
K:
WEG:
WEI:
Modified format by LRM in 6/2006 to include metric conversion and change permeability to saturated hydraulic conductivity.