LOCATION BONDOE MTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aridic Haplustalfs
TYPICAL PEDON: Bondoe channery loam, in rangeland (colors are for dry soil unless otherwise noted).
A--0 to 4 inches; light brownish gray (2.5Y 6/2) channery loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and few fine roots; many very fine and fine pores; 20 percent channers; neutral (pH 7.2); clear wavy boundary. (3 to 7 inches thick)
Bt--4 to 11 inches; grayish brown (2.5Y 5/2) channery clay loam, dark grayish brown (2.5Y 4/2) moist; strong medium prismatic structure; hard, friable, sticky and slightly plastic; many very fine and few fine roots; many very fine tubular and interstitial pores; common faint clay films on faces of peds; 20 percent channers; neutral (pH 7.2). (7 to 13 inches thick)
Bk--11 to 23 inches; grayish brown (2.5Y 5/2) very channery loam, dark grayish brown (2.5Y 4/2) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots; many very fine tubular and interstitial pores; 40 percent channers; disseminated lime; continuous distinct lime coatings on coarse fragments; strongly effervescent; slightly alkaline (pH 7.4); gradual irregular boundary. (12 to 15 inches thick)
C--23 to 60 inches; gray (10YR 5/1) very channery loam, dark grayish brown (2.5Y 4/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular and interstitial pores; 55 percent channers; slightly effervescent; slightly alkaline (pH 7.6).
TYPE LOCATION: Jefferson County, Montana; 1,600 feet south and 1,750 feet east of the NW corner of sec. 36, T. 2 N., R. 3 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 40 to 46 degrees F.
Moisture control section - between 4 and 12 inches, dry in all parts between four-tenths and five-tenths of the cumulative days per year when the soil temperature at a depth of 20 inches is 41 degrees F and higher.
Depth to argillic horizon - 3 to 7 inches.
Depth to the Bk horizon - 10 to 18 inches.
A horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry
Chroma: 2 or 3
Clay content: 18 to 25 percent
Rock fragments: 15 to 30 percent shale channers
Reaction: pH 6.6 to 7.3
Bt horizon - Hue: 10YR or 2.5Y
Value: 4 or 5
Chroma: 2 or 3
Texture: loam or clay loam
Clay content: 25 to 35 percent
Rock fragments: 15 to 35 percent shale channers
Reaction: pH 6.6 to 7.8
Bk horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3, or 4
Texture: loam or silt loam
Clay content: 18 to 27 percent
Rock fragments: 35 to 60 percent shale channers
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.4 to 8.4
C horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 1, 2, or 3
Texture: loam or silt loam
Clay content: 18 to 27 percent
Rock fragments: 35 to 60 percent shale channers
Calcium carbonate equivalent: 3 to 10 percent
Reaction: pH 7.4 to 8.4
COMPETING SERIES:
Ferball (MT) - is calcareous to the surface; is not loamy-skeletal below the argillic horizons.
GEOGRAPHIC SETTING:
Landform - alluvial fans; hills.
Elevation - 4,000 to 5,000 feet.
Slope- 4 to 15 percent.
Parent material - alluvium and colluvium derived from hard shale.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual air temperature - 40 to 44 degrees F.
Frost-free period - 90 to 115 days.
DRAINAGE AND PERMEABILITY: Well drained, moderately slow permeability.
USE AND VEGETATION: Bondoe soils are mainly used for rangeland and cropland. The potential native vegetation is mainly bluebunch wheatgrass, needleandthread, western wheatgrass, blue gramma, fringed sagewort, salsify, rubber rabbitbrush, and big sagebrush.
DISTRIBUTION AND EXTENT: Bondoe soils are of small extent
in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Jefferson County, Montana, 1993.
REMARKS: Soil interpretation record: MT1569. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the soil surface to 4 inches (A horizon); an argillic horizon from 4 to 11 inches (Bt horizon); a particle-size control section from 4 to 11 inches (Bt horizon); a horizon of secondary carbonate accumulations 11 to 23 inches (Bk horizon). Bondoe soils have a frigid temperature regime and an ustic moisture regime boarding on aridic.
Classification changed from Typic Eutroboralfs in 1997.