LOCATION MCCONAUGHY NEEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Aridic Haplustolls
TYPICAL PEDON: McConaughy loam with a slope of 12 percent, on a lower back slope, in rangeland. (Colors are for dry soil unless other wise stated.)
A1--0 to 15 centimeters (0 to 6 inches); grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to weak fine granular; slightly hard, friable; neutral; clear smooth boundary.
A2--15 to 33 centimeters (6 to 13 inches); grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to weak fine granular; slightly hard, friable; neutral; clear smooth boundary. (Combined thickness A horizon is 18 to 51 centimeters (7 to 20 inches)
Bw1--33 to 43 centimeters (13 to 17 inches); brown (10YR 5/3) loam, brown (10YR 4/3) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable; slight effervescence; slightly alkaline; clear smooth boundary.
Bw2--43 to 56 centimeters (17 to 22 inches); pale brown (10YR 6/3) very fine sandy loam, brown (10YR 5/3) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable; strong effervescence; moderately alkaline; gradual wavy boundary. (Combined thickness of the Bw horizon is 15 to 30 centimeters (6 to 12 inches.)
BC--56 to 86 centimeters (22 to 34 inches); very pale brown (10YR 7/3) loam, brown (10YR 5/3) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable; few small soft white accumulations of carbonates; violent effervescence; strongly alkaline; gradual wavy boundary. (15 to 36 centimeters (6 to 14 inches) thick.)
C1--86 to 102 centimeters (34 to 40 inches); very pale brown (10YR 7/3) very fine sandy loam, brown (10YR 5/3) moist; massive; slightly hard, friable; few small soft white accumulations of carbonates; strong effervescence; moderately alkaline; diffuse wavy boundary.
C2--102 to 152 centimeters (40 to 60 inches); very pale brown (10YR 7/3) very fine sandy loam, brown (10YR 5/3) moist; massive; slightly hard, friable; few small soft white accumulations of carbonates; strong effervescence; strongly alkaline.
TYPE LOCATION: Keith County, Nebraska; about 11 kilometers (7 miles) west and 13 kilometers (8 miles) north of Brule; 145 meters (475 feet) east and 384 meters (1260 feet) south of the northwest corner of section 4, T. 14 N., R. 41 W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 11 to 12 degrees C. (51 to 53 degrees F.)
Depth to mollic epipedon: 18 to 51 centimeters (7 to 20 inches)
Depth to secondary calcium carbonate: 25 to 46 centimeters (10 to 18 inches)
Depth to cambic horizon: 18 to 51 centimeters (7 to 20 inches)
Clay content: 10 to 18 percent
A horizon:
Hue: 10YR
Value: 4 or 5 (2 or 3 moist)
Chroma: 2 or 3
Texture: loam or very fine sandy loam
Reaction: neutral or slightly alkaline
Bw horizon:
Hue: 10YR
Value: 5 to 7, (4 or 5 moist)
Chroma: 2 or 3
Texture: loam or very fine sandy loam
Clay content: 10 to 18 percent
Reaction: slightly or moderately alkaline
BC and C horizon:
Hue: 10YR
Value: 5 to 7, (4 or 5 moist)
Chroma: 2 to 4
Texture: loam or very fine sandy loam
Calcium carbonate equivalent: 1 to 5 percent
Reaction: moderately or strongly alkaline
Some pedons have a Bk horizon.
COMPETING SERIES: These are the
Oglala and
Tripp series.
Oglala soils have soft fine grained sandstone at depths of 102 to 152 centimeters (40 to 60 inches).
Tripp soils have carbonates at depths of 46 to 102 centimeters (18 to 40 inches) and are on stream terraces.
GEOGRAPHIC SETTING:
Parent material: derived from loamy calcareous loess
Landform: on gently sloping to moderately steep upland back slopes and the upper part of foot slopes
Slopes: 3 to 15 percent
Elevation: 914 to 1219 meters (3000 to 4000 feet)
Mean annual temperature: 10 to 11 degrees C. (49 to 51 degrees F)
Mean annual precipitation: 43 to 48 centimeters (17 to 19 inches)
Frost-free period: 130 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Duroc, keith and
Sulco series.
Duroc soils have a mollic epipedon more than 51 centimeters (20 inches) thick and are on toe slopes or swales positions on the landscape.
Keith soils have an argillic horizon and are on summits.
Sulco soils do not have a mollic epipedon, are on upper side slopes and on shoulders.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Saturated hydraulic conductivity: moderately high
Runoff: medium
USE AND VEGETATION: Most areas of McConaughy soils are in rangeland. Some small areas are in cropland. The native grasses are mainly little bluestem, blue grama, western wheatgrass, big bluestem, and needleandthread.
DISTRIBUTION AND EXTENT: Western Nebraska and possibly Kansas and northeastern Colorado. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Keith County, Nebraska, 1990
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 18 to 51 centimeters (7 to 20 inches) (Ap, A1, A2 horizon)
Cambic horizon: 33 to 56 centimeters (13 inches to 22 inches) (the Bw horizon)
This soil was previously included with the Ulysses series.
ADDITIONAL DATA: Pedon S88NE-101-14 described and sampled for NSSL characterization.
Modified format by LRM in 1/2006 to include metric conversion and change permeability to saturated hydraulic conductivity.