LOCATION HEDSTROM MTEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Typic Argiustolls
TYPICAL PEDON: Hedstrom loam, in pasture. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 7 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine angular blocky structure parting to moderate fine granular; soft, friable, nonsticky and slightly plastic; many very fine roots; neutral (pH 7.0); abrupt smooth boundary. (4 to 7 inches thick)
Bt1--7 to 15 inches; brown (10YR 5/3) sandy clay loam, dark brown (10YR 3/3) moist; weak coarse prismatic structure parting to moderate coarse angular blocky; slightly hard, friable, slightly sticky and plastic; common very fine roots; common very fine pores; common thin clay films on faces of peds and in pores; neutral (pH 7.2); abrupt smooth boundary. (6 to 9 inches thick)
Bt2--15 to 22 inches; brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; moderate medium coarse prismatic structure; slightly hard, friable, sticky and plastic; common very fine roots; many very fine pores; many thin clay films on faces of peds and in pores; neutral (pH 7.2); clear smooth boundary. (5 to 14 inches thick)
Bk--22 to 31 inches; light gray (10YR 7/2) loam, grayish brown (10YR 5/2) moist; moderate medium angular blocky structure; slightly hard, friable, slightly sticky and plastic; common very fine roots; many very fine pores; many medium soft masses of lime; violently effervescent; moderately alkaline (pH 8.4). (5 to 10 inches thick)
2C--31 to 60 inches; pale brown (10YR 6/3) fine sand, brown
(10YR 5/3) moist; single grain; loose, nonsticky and nonplastic; few very fine roots; 5 percent pebbles; thin lime coatings on surface of pebbles; strongly effervescent; mildly alkaline (pH 7.8).
TYPE LOCATION: Prairie County, Montana; 2,350 feet west and 300 feet south of the NE corner of sec. 6, T. 16 N., R. 50 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - approximately between the depths of 4 and 12 inches
Mollic epipedon thickness - 10 to 16 inches (includes part of the Bt horizon)
Depth to Bk horizon - 15 to 30 inches
Depth to 2C horizon - 20 to 40 inches
A horizon - Value: 4 dry; 2 or 3 moist
Chroma: 2 or 3
Texture, less than 2 mm: fine sandy loam or loam
Clay content: 15 to 27 percent
Rock fragments: 0 to 10 percent pebbles
Reaction: pH 6.6 to 7.3
Bt horizons - Hue: 10YR or 2.5Y
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2, 3, or 4
Texture, less than 2 mm: sandy clay loam or clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 10 percent pebbles
Reaction: pH 6.6 to 7.8
Bk horizon - Hue: 10YR or 2.5 Y
Value: 6 or 7 dry; 4, 5, or 6 moist
Chroma: 2, 3, or 4
Texture, less than 2 mm: sandy clay loam or loam
Clay content: 20 to 30 percent
Rock fragments: 0 to 10 percent pebbles
EC: less than 4 mmhos/cm
Calcium carbonate equivalent: 8 to 15 percent
Reaction: pH 7.9 to 9.0
2C horizon - Hue: 10YR or 2.5Y
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2 or 3
Texture, less than 2 mm: sand, fine sand, or loamy fine sand
Clay content: 0 to 5 percent
Rock fragments: 0 to 15 percent pebbles
EC: less than 4 mmhos/cm
Reaction: pH 7.4 to 8.4
COMPETING SERIES: The Turner series is the only competing series. Turner soils have more than 35 percent rock fragments in the 2C horizon. The Degrand series is closely similar and has an aridic moisture regime.
GEOGRAPHIC SETTING: Hedstrom soils are on fans and terraces. Elevations are 2,540 to 3,500 feet. Slopes are 0 to 8 percent. These soils formed in mixed loamy alluvium and are 20 to 40 inches thick over sand, fine sand, or loamy fine sand. The climate is characterized by long, cold winters; moist springs; and warm summers. Mean annual precipitation is 12 to 16 inches. Mean annual temperature is 40 to 45 degrees F. The frost-free period is 90 to 110 days.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability in the A and B horizons and rapid permeability in the 2C horizon.
USE AND VEGETATION: Hedstrom soils are used mainly as rangeland and for dryland crops. The potential native vegetation is bluebunch wheatgrass, western wheatgrass, green needlegrass, needleandthread, and some forbs and shrubs.
DISTRIBUTION AND EXTENT: Hedstrom soils are of small extent in southeastern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES PROPOSED: Prairie County, Montana, 1984. Hedstrom is the name of a lake in Prairie County.
REMARKS: Soil Interpretation Records: MT0874. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 15 inches (Ap, Bt1 horizons); an argillic horizon from 7 to 22 inches (Bt1, Bt2 horizons); a particle-size control section from 7 to 40 inches (Bt1, Bt2, Bk, and 2C horizons). Hedstrom soils have a frigid temperature regime and an ustic moisture regime.