LOCATION BITTON MT+UT WYEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Entic Haplustolls
TYPICAL PEDON: Bitton gravelly loam, in rangeland (colors are for dry soil unless otherwise noted).
A1--0 to 4 inches; dark grayish brown (10YR 4/2) gravelly loam, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine roots; 15 percent pebbles; slightly effervescent; slightly alkaline (pH 7.6); abrupt smooth boundary.
A2--4 to 11 inches; grayish brown (10YR 5/2) gravelly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; 20 percent pebbles; slightly effervescent; slightly alkaline (pH 7.8); gradual wavy boundary. (Combined thickness of the A horizons is 7 to 15 inches)
Bw--11 to 21 inches; grayish brown (10YR 5/2) gravelly loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; 25 percent pebbles; strongly effervescent with disseminated lime; moderately alkaline (pH 8.4); clear wavy boundary. (4 to 15 inches thick)
Bk--21 to 46 inches; pale brown (10YR 6/3) very gravelly loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; soft, friable, sticky and plastic; common very fine roots; 65 percent pebbles; lime casts on undersides of pebbles and disseminated lime; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (10 to 30 inches thick)
BCk--46 to 60 inches; pale brown (10YR 6/3) gravelly loam stratified with gravelly sandy loam, yellowish brown (10YR 5/4) moist; massive; slightly hard, friable, nonsticky and slightly plastic; few very fine roots; 45 percent pebbles; lime casts on undersides of pebbles, disseminated lime; strongly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Big Horn County, Montana; on west side of ridge; approximately 1,300 feet south and 1,000 feet east of the NW corner of sec. 34, T. 4 S., R. 36 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 40 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 15 inches.
Depth to Bk horizon - 11 to 28 inches.
Soil phases - stony, gravelly, loamy substratum, cool, warm.
A BC transition horizon is allowed.
A horizons - Hue: 10YR, 2.5Y, 7.5YR, or 5YR
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3
Texture: loam or clay loam
Clay content: 12 to 32 percent
Rock fragments: 0 to 45 percent--0 to 20 percent stones and cobbles; 5 to 45 percent channers and pebbles
Reaction: pH 6.6 to 8.4
Bw horizon - Hue: 10YR, 2.5Y, 7.5YR, or 5YR
Value: 4, 5, or 6 dry; 4 or 5 moist
Chroma: 2, 3, or 4
Clay content: 12 to 27 percent
Rock fragments: 20 to 60 percent--0 to 10 percent stones and cobbles; 20 to 60 percent channers and pebbles
Reaction: pH 7.4 to 8.4
Bk, BCk horizons - Hue: 10YR, 2.5Y, 7.5YR, or 5YR
Value: 5, 6, 7, or 8 dry; 4, 5, 6, 7, or 8 moist
Chroma: 2, 3 or 4
Texture: loam or sandy loam
Clay content: 10 to 27 percent
Rock fragments: 35 to 75 percent--0 to 60 percent cobbles and stones; 35 to 60 percent pebbles and channers
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.4 to 8.4 above 40 inches and 7.4 to 9.0 below. (WY has pH 8.5 to 9.0 below 28 inches.)
COMPETING SERIES:
Datino (UT) - has carbonates above a depth of 11 inches.
Heely (SD) - 20 to 40 inches deep over schist bedrock.
Labre (MT) - has a calcic horizon.
Osha (NM) - 20 to 40 inches deep to bedrock.
Perma (MT) - is noncalcareous above a depth of 40 inches.
Pesmore (WY) - 20 to 40 inches deep to bedrock.
Peso (NM) - 20 to 40 inches deep to bedrock.
Pesowyo (WY) - 20 to 40 inches deep to bedrock.
Sandia (NM) - more than 50 percent cobbles and stones in the control section; chroma of 1 in the mollic epipedon.
Slimbutte (SD) - is fragmental below a depth of 40 inches.
Subwell (MT) - has a calcic horizon and a lithological discontinuity at depths of 10 to 20 inches.
Veatch (CO) - 20 to 40 inches deep to bedrock.
Vigilante (MT) - has a lithic contact at 40 to 60 inches; does not have horizon of carbonate accumulation.
Wanagan (ND) - has a lithological discontinuity at depths of 12 to 20 inches; has a Bk horizon less than 13 inches thick.
Wimper (MT) - has a calcic horizon.
GEOGRAPHIC SETTING:
Landform - alluvial fans, stream terraces, treads, terrace risers and hills.
Elevation - 2,900 to 4,700 feet. (In Wyoming and Utah it ranges to 8,200 feet.)
Slope- 0 to 70 percent.
Parent material - alluvium and colluvium from mixed rock sources such as sandstone and shale.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 12 to 19 inches.
Mean annual air temperature - is 38 to 45 degrees F.
Frost-free period - 90 to 135 days. (In Wyoming and Utah it is 60 to 90 days.)
DRAINAGE AND PERMEABILITY: Well-drained; moderate permeability.
USE AND VEGETATION: Bitton soils are used for rangeland. Potential native vegetation is bluebunch wheatgrass, green needlegrass, rough fescue, Idaho fescue, needleandthread, little bluestem, forbs, and shrubs.
DISTRIBUTION AND EXTENT: Bitton soils are moderately extensive in central Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Big Horn County (Big Horn Area), Montana, 1970.
REMARKS: Soil interpretation records: MT0082, MT0462, MT1149, MT0143, MT0366.
Diagnostic horizons and features recognized in this pedon are: mollic epipedon - from the soil surface to 11 inches (A1, A2 horizons); cambic horizon - from 11 to 21 inches (Bw horizon); horizon of carbonate accumulation - from 21 to 60 inches (Bk, BCk horizons); particle-size control section - from 10 to 40 inches (A2, Bw, Bk horizons). Bitton soils have a frigid temperature regime and an ustic moisture regime.