LOCATION BULLTOP NDEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Aridic Haplustolls
TYPICAL PEDON: Bulltop loam - on a 8 percent southwest facing slope, in rangeland (Colors are for dry soil unless otherwise stated. When described the soil was dry throughout.)
A--0 to 4 inches; brown (10YR 4/3) loam, dark brown (10YR 3/3) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine roots throughout; many very fine tubular pores; 18 percent clay; 3 percent limestone-sandstone gravel; neutral; clear smooth boundary. (3 to 6 inches thick)
Bw1--4 to 8 inches; brown (10YR 4/3) loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots throughout; common very fine tubular pores; 18 percent clay; 3 percent limestone-sandstone gravel; slightly alkaline; clear smooth boundary.
Bw2--8 to 15 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots throughout; common very fine tubular pores; 18 percent clay; 3 percent limestone-sandstone gravel; slightly alkaline; clear wavy boundary. (Combined Bw horizons 8 to 16 inches thick)
2BCk--15 to 19 inches; light olive brown (2.5Y 5/3) gravelly loam, olive brown (2.5Y 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots throughout; common very fine tubular pores; 18 percent clay; few carbonate coats on lower surfaces of peds or rocks; strongly effervescent throughout (HCL, 1 normal); 25 percent limestone-sandstone gravel; moderately alkaline; gradual wavy boundary. (0 to 20 inches thick)
2C--19 to 80 inches; light gray (2.5Y 7/2) very gravelly loam, grayish brown (2.5Y 5/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots throughout; 18 percent clay; strongly effervescent throughout (HCL, 1 normal); 45 percent limestone-sandstone gravel and 5 percent limestone-sandstone cobbles; moderately alkaline.
TYPE LOCATION: Golden Valley County, North Dakota; 2,110 feet east and 1,475 feet north of the southwest corner, sec. 8, T. 139 N., R. 103 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 40 to 45 degrees F.
Mollic thickness - 7 to 16 inches
Depth to gravelly material - 10 to 18 inches
Particle-size control section - averages 18 to 27 percent clay
A horizon - Hue 10YR
Value: 4 or 5 (3 moist)
Chroma: 2 or 3
Texture: loam or silt loam
Percent rock fragments: 0 to 5
Reaction - slightly acid or neutral
Bw horizon - Hue 10YR or 2.5Y
Value: 4 or 5 (3 or 4 moist)
Chroma: 2 or 3
Texture: loam or silt loam
Percent rock fragments: 0 to 30
Reaction - neutral or slightly alkaline
Some pedons have a 2Bw horizon.
2BCk horizon - Hue 2.5Y
Value: 5 to 7 (4 or 5 moist)
Chroma: 3 or 4
Texture: loam or coarse sandy loam
Percent rock fragments: 20 to 70
Reaction - slightly alkaline or moderately alkaline
Some pedons have a Bk or 2Bk horizon.
2C horizon - Hue 2.5Y
Value: 5 to 7 (4 to 6 moist)
Chroma: 2 to 4
Texture: loam or sandy loam
Percent rock fragments: 45 to 75
Reaction - slightly alkaline or moderately alkaline
COMPETING SERIES:
Dolus - has a paralithic contact of semiconsolidated interbedded sandstone and siltstone at depths of 20 to 40 inches.
Sixbeacon - has a lithological discontinuity in the Bk horizon: has less than 18 percent clay in the particle-size control section.
GEOGRAPHIC SETTING:
Landform - fans and terraces.
Elevation - 2,500 to 3,500 feet.
Slope- 1 to 15 percent.
Parent material - alluvium.
Climate - cool, with long, cold winters; moist springs; warm summers.
Mean annual precipitation - 13 to 16 inches.
Mean annual air temperature - 40 to 45 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boxwell, Cabbart, Kremlin and Shibah soils. Boxwell soils are on side slopes of uplands. They have soft bedrock at depths of 20 to 40 inches. Cabbart soils are on knobs and ridges of uplands. They have soft bedrock at depths of 10 to 20 inches. Kremlin soils are intermixed with the Bulltop series. They have up to 5 percent rock fragments throughout the profile. Shibah soils are intermixed with the Bulltop series. They do not have a cambic horizon.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate in the upper part and rapid in the underlying material.
USE AND VEGETATION: Bulltop soils are used for rangeland. The potential native vegetation is mainly western wheatgrass and green needlegrass.
DISTRIBUTION AND EXTENT: Southwestern North Dakota. Bulltop soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Billings County, North Dakota, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the soil surface to a depth of 15 inches (A, Bw1 and Bw2 horizons); accumulation of lime - from 15 to 19 inches (2BCk horizon); particle-size control section - from 10 to 40 inches (Bw2, 2BCk and 2C horizons).