LOCATION BABB MT+UT WY
Established Series
Rev. RJE-JAL-RJS
01/2012
BABB SERIES
The Babb series consists of very deep, well drained soils that formed in alpine till and colluvium derived from a mixture of argillite, quartzite, limestone, and calcareous shale. These soils are on alluvial fans, fan remnants, hills, moraines and mountains. Slopes are 2 to 70 percent. Mean annual precipitation is about 17 inches, and mean annual air temperature is about 38 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Calcic Haplocryolls
TYPICAL PEDON: Babb cobbly loam, grassland (colors are for dry soil unless otherwise noted).
A--0 to 7 inches; black (10YR 2/1) cobbly loam, black (10YR 2/1) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine roots; many fine interstitial pores; 15 percent gravel and 15 percent cobbles; neutral (pH 7.0); clear irregular boundary. (5 to 12 inches thick)
Bw1--7 to 15 inches; dark grayish brown (10YR 4/2) gravelly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine roots; common fine and medium interstitial pores, and few fine tubular pores; 15 percent gravel and 10 percent cobbles; neutral (pH 7.0); clear wavy boundary.
Bw2--15 to 21 inches; grayish brown (10YR 5/2) gravelly loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots; common fine and medium interstitial pores, and few fine tubular pores; 20 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.6); abrupt wavy boundary. (combined thickness of Bw1, Bw2 - 9 to 22 inches)
Bk--21 to 60 inches; very pale brown (10YR 8/2) gravelly loam, light brownish gray (10YR 6/2) moist; weak medium platy structure becoming moderate in the lower part; very hard, friable, slightly sticky and slightly plastic; few very fine roots with concentrations of roots in vertical cracks; 20 percent gravel and 5 percent cobbles; finely disseminated calcium carbonate, and calcium carbonate coats on rock fragments; violently effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Glacier County, Montana; 400 feet east and 300 feet south of the northwest corner of sec. 14, T. 35N, R. 14W.
RANGE IN CHARACTERISTICS:
Soil temperature - 38 to 42 degrees F.
Mollic epipedon thickness - 10 to 16 inches (may include Bw1 horizon)
Depth to secondary calcium carbonate accumulation - 16 to 30 inches
A horizon
Value: 2, 3 or 4 dry; 1, 2 or 3 moist
Chroma: 1 or 2; dry or moist
Texture: loam or silt loam
Clay content: 18 to 27 percent
Rock fragments: 5 to 60 percent--5 to 35 percent gravel, 0 to 25 percent cobbles
Reaction: pH 6.6 to 7.8
Bw1, Bw2 horizons
Hue: 2.5Y, 10YR or 7.5Y
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2, 3 or 4; dry or moist
Texture: loam or clay loam
Clay content: 18 to 32 percent
Rock fragments: 10 to 35 percent--10 to 25 percent gravel, 0 to 10 percent cobbles
Calcium carbonate equivalent: 0 to 3 percent
Reaction: pH 6.6 to 7.8
Bk horizon
Hue: 2.5Y, 10YR or 7.5Y
Value: 7 or 8 dry; 5 or 6 moist
Chroma: 2 or 3; dry or moist
Texture: loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 15 to 60 percent--10 to 50 percent gravel, 0 to 10 percent cobbles
Calcium carbonate equivalent: 20 to 40 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Prudy (ID) - deep to a duripan
GEOGRAPHIC SETTING:
Landform - alluvial fans, fan remnants, hills, moraines and mountains
Elevations - 4,500 to 7,400 feet
Slope - 2 to 70 percent
Parent material - alpine till and colluvium derived from a mixture of argillite, quartzite, limestone, and calcareous shale
Climate - long, cold winters; moist springs; cool summers
Mean annual precipitation - 15 to 24 inches
Mean annual air temperature - 36 to 40 degrees F.
Frost-free period - 50 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: None.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Babb soils are used mainly as rangeland. Potential native vegetation is mainly rough fescue, bluebunch wheatgrass, Columbia needlegrass, and Idaho fescue. Aspen are in some places.
DISTRIBUTION AND EXTENT: Babb soils are of moderate extent along the eastern front of the Rocky Mountains in Montana. MLRAs - 43B, 44B, 46.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Glacier County, Montana, 1970.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 15 inches (A, Bw1 horizons)
Cambic horizon - from 15 to 21 inches (Bw2 horizon)
Calcic horizon - from 21 to 60 inches (Bk horizon)
Particle-size control section - from 10 to 40 inches (part of Bw1, Bw2, part of Bk horizons)
Babb soils have a cryic temperature regime and an ustic moisture regime.
ADDITIONAL DATA: Soil interpretations records - MT0457, MT1085, MT0832.
National Cooperative Soil Survey
U.S.A.