LOCATION BANGTAIL MTEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive Ustic Argicryolls
TYPICAL PEDON: Bangtail loam, in rangeland (Colors are for dry soil unless otherwise noted).
A--0 to 9 inches; very dark grayish brown (10YR 3/2) loam, black (10YR 2/1) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine and few medium roots; many very fine, common fine and few medium pores; 5 percent channers, 10 percent soft shale chips; slightly acid (pH 6.4); clear smooth boundary. (6 to 14 inches thick)
Bt1--9 to 14 inches; brown (10YR 4/3) clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine and fine and few medium roots; many very fine and few fine and medium pores; few faint clay films on faces of peds; 5 percent channers, 10 percent soft shale chips; slightly acid (pH 6.4); clear smooth boundary.
Bt2--14 to 23 inches; dark yellowish brown (10YR 4/4) clay loam, dark yellowish brown (10YR 3/4) moist; moderate medium subangular blocky structure; slightly hard, friable, very sticky and very plastic; common very fine and fine and few medium roots; common very fine and few fine and medium pores; common distinct clay films on faces of peds; 5 percent channers, 15 percent soft shale chips; slightly acid (pH 6.4); clear wavy boundary. (Combined thickness of Bt horizons is 14 to 30 inches).
C--23 to 37 inches; light olive brown (2.5Y 5/4) clay loam, olive brown (2.5Y 4/4) moist; weak medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common very fine and fine and few medium roots; common very fine and few fine and medium pores; 5 percent channers; 20 percent soft shale chips; neutral (pH 6.8); gradual wavy boundary. (0 to 15 inches thick)
Cr-- 37 to 60 inches; olive yellow (2.5Y 6/6) interbedded soft shale and fine grained sandstone; neutral (pH 6.8).
TYPE LOCATION: Gallatin County, Montana; 1200 feet west and 2100 feet north of the SE corner of sec. 24, T.2S.,R.7E.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 36 to 40 degrees F.
Mean summer soil temperature - 52 to 58 degrees F.; moist phase is 45 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 8 to 15 inches.
Depth to Cr horizon - 20 to 40 inches.
A horizon - Value: 3, 4 or 5 dry; 2 or 3 moist
Chroma: 1, 2 or 3
Texture: Loam or clay loam
Clay content: 18 to 35 percent
Rock fragments: 5 to 30 percent--10 to 20 percent soft shale chips, 5 to 15 percent channers or pebbles, 0 to 5 percent flagstones or cobbles, 0 to 5 percent stones
Reaction: pH 5.6 to 7.3
Bt1 horizon - Hue: 10YR or 2.5Y
Value: 4, 5 or 6 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: clay loam or clay
Clay content: 35 to 50 percent
Rock fragments: 5 to 25 percent-- 5 to 15 percent channers or pebbles, 0 to 10 percent flagstones or cobbles; 10 to 20 percent soft shale chips
Reaction: pH 5.6 to 7.3
Bt2 horizon - Hue: 10YR or 2.5Y
Value: 4, 5 or 6 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: clay loam or clay
Clay content: 35 to 50 percent
Rock fragments: 5 to 25 percent-- 5 to 15 percent channers or pebbles, 0 to 10 percent flagstones or cobbles; 10 to 20 percent soft shale chips
Reaction: pH 6.1 to 7.3
C horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: clay loam or clay
Clay content: 27 to 45 percent
Rock fragments: 5 to 25 percent--5 to 15 percent channers or pebbles, 0 to 10 percent flagstones or cobbles, 10 to 25 percent soft shale chips.
Reaction: pH 6.1 to 7.3
COMPETING SERIES:
Bridger (MT) - does not have a paralithic contact above 60 inches; has horizons of secondary carbonate accumulation.
Duckcreek (MT) - has horizon of secondary carbonate accumulation.
Echard (UT) - does not have a paralithic contact above 60 inches; formed in soft rhyolitic tuff or strongly cemented ash.
Melville (MT) - does not have a paralithic contact above 60 inches; has horizon of secondary carbonate accumulation.
Mollet (MT) - does not have a paralithic contact above 60 inches.
Rattler (MT) - does not have a paralithic contact above 60 inches; has horizons of secondary carbonate accumulation.
Sevier (UT) - has Bt horizon which is 4 to 10 inches thick; is moderately well drained.
GEOGRAPHIC SETTING:
Landform - hills, mountains, escarpments.
Elevation - 5,200 to 8,300 feet.
Slope - 4 to 60 percent.
Parent material - residuum derived from cretaceous interbedded shale and sandstone.
Climate - long, cold winters; cool, moist springs; short summers.
Mean annual precipitation - 17 to 24 inches.
Mean annual air temperature - 34 to 38 degrees F.
Frost-free period - 50 to 70 days.
DRAINAGE AND PERMEABILITY: Well drained; slow permeability.
USE AND VEGETATION: Bangtail soils are used mainly for rangeland and wildlife habitat. Potential native vegetation may include Idaho fescue, Richardson needlegrass, Columbia needlegrass, mountain brome, lupine, and sticky geranium.
DISTRIBUTION AND EXTENT: Bangtail soils are of small extent in southwestern Montana.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Gallatin County, Montana, 1997.
REMARKS: Soil interpretation record: MT1458. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the surface to 14 inches (A and Bt1 horizons); an argillic horizon which is the particle-size control section from 9 to 23 inches (Bt1 and Bt2 horizons); a layer of interbedded soft shale and sandstone from 37 to 60 inches (Cr horizon). Bangtail soils have a cryic temperature regime and an ustic moisture regime.