LOCATION CETRACK MTEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Aridic Haplustolls
TYPICAL PEDON: Cetrack loam, irrigated pasture (colors are for dry soil unless otherwise noted).
Ap--0 to 6 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; slightly hard, very friable, slightly sticky and slightly plastic; neutral (pH 7.1); abrupt smooth boundary. (4 to 6 inches thick)
Bw--6 to 12 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; 5 percent pebbles; few wormcasts; slightly alkaline (pH 7.5); gradual smooth boundary. (4 to 8 inches thick)
Bk1--12 to 16 inches; pale brown (10YR 6/3) loam, dark brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; 5 percent pebbles; few medium threads and nodules of lime; strongly effervescent; moderately alkaline (pH 7.9); gradual smooth boundary. (4 to 8 inches thick)
Bk2--16 to 32 inches; light gray (10YR 7/2) loam, brown (10YR 5/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; 10 percent pebbles; many fine lime nodules; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (8 to 18 inches thick)
2C--32 to 60 inches; light gray (10YR 7/2) very gravelly loamy sand, grayish brown (10YR 5/2) moist; single grain; loose, nonsticky and nonplastic; 40 percent pebbles and 20 percent cobbles; common distinct lime coatings on rock fragments; strongly effervescent in upper part; slightly alkaline (pH 7.6).
TYPE LOCATION: Granite County, Montana; 2,310 feet east and 2,310 feet south of the NW corner of sec. 6, T. 10 N., R. 12 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - between 4 and 12 inches, dry in all parts less than five-tenths and dry in some part more than six-tenths of the cumulative days per year when the soil temperature at a depth of 20 inches is 41 degrees F or higher.
Mollic epipedon thickness - 7 to 14 inches.
Rock fragments - less than 35 percent in the control section.
Depth to very gravelly material - 20 to 40 inches.
Depth to calcic horizon - 8 to 14 inches.
Ap horizon - Chroma: 2 or 3
Clay content: 15 to 25 percent
Rock fragments: 0 to 25 percent--0 to 5 percent cobbles; 0 to 20 percent pebbles.
Reaction: pH 6.1 to 7.3
Bw horizon - Hue: 7.5YR, 10YR, or 2.5Y
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 2 or 3
Texture: loam or clay loam
Clay content: 22 to 32 percent
Rock fragments: 0 to 20 percent--0 to 5 percent cobbles; 0 to 15 percent pebbles
Reaction: pH 6.6 to 7.8
Bk1 horizon - Hue: 10YR or 2.5Y
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam or clay loam
Clay content: 22 to 32 percent
Rock fragments: 5 to 20 percent--0 to 5 percent cobbles; 5 to 15 percent pebbles
Calcium carbonate equivalent: 5 to 20 percent
Reaction: pH 7.4 to 8.4
Bk2 horizon - Hue: 10YR or 2.5Y
Value: 7 or 8 dry; 5 or 6 moist
Chroma: 2 or 3
Clay content: 18 to 25 percent
Rock fragments: 5 to 25 percent--0 to 5 percent cobbles; 5 to 20 percent pebbles
Calcium carbonate equivalent: 15 to 30 percent
Reaction: pH 7.9 to 8.4
2C horizon - Hue: 10YR or 2.5Y
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2, 3, or 4
Texture: loamy sand or sand
Clay content: 0 to 15 percent
Rock fragments: 35 to 70 percent--0 to 20 percent cobbles; 35 to 50 percent pebbles
Reaction: pH 7.4 to 8.4
COMPETING SERIES:
Chanta (ND) - has less than 15 percent CaCO3 equivalent above the 2C horizon.
GEOGRAPHIC SETTING:
Landform - alluvial fans; stream terraces; glacial outwash plains.
Elevation - 3,000 to 5,600 feet.
Slope- 0 to 15 percent.
Parent material - calcareous alluvium. They have sands and gravel at moderate depths.
Climate - long, cold winters; moist springs; hot, dry summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual air temperature - 40 to 45 degrees F.
Frost-free period - 90 to 105 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability in the Bw and Bk horizons and rapid below.
USE AND VEGETATION: Cetrack soils are used mainly for irrigated cropland; some areas are used for rangeland. Potential native vegetation is mainly bluebunch wheatgrass, green needlegrass, needleandthread, Sandberg bluegrass, prairie junegrass, and forbs.
DISTRIBUTION AND EXTENT: Cetrack soils are moderately extensive in mountain valleys of western Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Powell, County, Montana, 1995. Series proposed: Upper Clark Fork River area, Montana, 1978.
REMARKS: Soil interpretations records: MT0619, MT8130. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 12 inches (Ap, Bw horizon); accumulation of lime from 12 to 32 inches (Bk1, Bk2 horizons); a particle-size control section from 10 to 40 inches (Bw, Bk1, Bk2 horizons). Cetrack soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.
ADDITIONAL DATA: Laboratory data S88MT-077-963, S91MT-023-005 (heavy metal).