LOCATION WINDHAM MT+WYEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, frigid Typic Calciustolls
TYPICAL PEDON: Windham gravelly clay loam, cultivated (colors are for dry soil unless otherwise noted).
Ap--0 to 6 inches; dark grayish brown (10YR 4/2) gravelly clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; 15 percent limestone pebbles; continuous distinct lime casts on undersides of pebbles; slightly effervescent; slightly alkaline (pH 7.8); clear wavy boundary. (5 to 10 inches thick)
Bk1--6 to 12 inches; pale brown (10YR 6/3) gravelly clay loam, brown (10YR 5/3) moist; moderate fine and very fine subangular blocky structure; hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine pores; 20 percent limestone pebbles; continuous prominent casts and pendants on undersides of pebbles; disseminated lime; violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary.
Bk2--12 to 18 inches; white (10YR 8/2) extremely gravelly loam, very pale brown (10YR 7/3) moist; massive; hard, friable, slightly sticky and nonplastic; many fine and very fine roots; many fine and very fine pores; 55 percent limestone pebbles, 5 percent limestone cobbles; common fine masses of lime; continuous prominent lime casts and pendants on underside of pebbles and cobbles; disseminated lime; violently effervescent; moderately alkaline (pH 8.4); diffuse wavy boundary. (Combined thickness of the Bk1 and Bk2 horizons is 15 to 33 inches.)
Bk3--18 to 61 inches; very pale brown (10YR 7/4) extremely gravelly loam, light yellowish brown (10YR 6/4) moist; massive; slightly hard, friable, slightly sticky and nonplastic; common fine and very fine roots; common to few fine and very fine pores; 60 percent limestone pebbles, 10 percent cobbles; common fine masses of lime; continuous distinct lime casts and pendants on undersides of pebbles and cobbles; disseminated lime; violently effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Fergus County, Montana; 33 feet north and 595 feet west of the SE corner of sec. 12, T. 15 N., R. 17 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 38 to 46 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 16 inches.
Depth to calcic horizon - 5 to 10 inches.
Surface stones or boulders - 0 to 3 percent
Ap horizon - Hue: 7.5YR, 10YR or 2.5Y
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1, 2, or 3
Texture: loam or clay loam
Clay content: 15 to 35 percent
Rock fragments: 10 to 75 percent--0 to 15 percent stones, 0 to 20 percent cobbles, 10 to 50 percent pebbles
Calcium carbonate equivalent: 5 to 10 percent
Reaction: pH 7.4 to 8.4
Bk1 horizon - Hue: 7.5YR, 10YR, or 2.5Y
Value: 4, 5, 6 or 7 dry; 3, 4, 5, or 6 moist
Chroma: 2, 3, or 4
Texture: loam or clay loam
Clay content: 15 to 35 percent
Rock fragments: 10 to 75 percent--0 to 20 percent cobbles, 10 to 55 percent pebbles
Calcium carbonate equivalent: 35 to 60 percent
Reaction: pH 7.9 to 8.4
Bk2 horizon - Hue: 7.5YR, 10YR, or 2.5Y
Value: 5, 6, 7, or 8 dry; 4, 5, 6, or 7 moist
Chroma: 2, 3, or 4
Texture: loam, clay loam, or sandy loam
Clay content: 15 to 35 percent
Rock fragments: 35 to 75 percent--0 to 30 percent cobbles; 35 to 55 percent pebbles
Calcium carbonate equivalent: 40 to 60 percent
Reaction: pH 7.9 to 8.4
Bk3 horizon - Hue: 7.5YR, 10YR, or 2.5Y
Value: 5, 6, 7, or 8 dry; 4, 5, 6, or 7 moist
Chroma: 2, 3, or 4
Texture: loam, clay loam, or sandy loam
Clay content: 15 to 35 percent
Rock fragments: 60 to 80 percent--5 to 20 percent cobbles; 55 to 60 percent pebbles
Calcium carbonate equivalent: 25 to 60 percent
Reaction: pH 7.9 to 9.0
COMPETING SERIES:
Clyl (UT) - has precipitation evenly distributed throughout the year.
Maiden (MT) - has a lithic contact at depths of 20 to 40 inches.
GEOGRAPHIC SETTING:
Landform - alluvial fans, stream terraces, escarpments, ridges, divides, hills, mountains.
Elevation - 3,000 to 6,800 feet.
Slope- 0 to 85 percent.
Parent material - alluvium and colluvium derived mainly from limestone but also from marly siltstone and other limy sedimentary rock.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 14 to 22 inches.
Mean annual temperature - 36 to 45 degrees F.
Frost-free season - 70 to 130 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Windham soils are used mainly as rangeland. A few small areas are used as cropland when in complex with other soils. Potential native vegetation is bluebunch wheatgrass, western wheatgrass, needleandthread, blue grama, prairie junegrass, shrubs, and forbs.
DISTRIBUTION AND EXTENT: It is of moderate extent in Montana and Wyoming..
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Big Horn County Area, Montana, 1970.
REMARKS: Soil interpretation records: MT0174, MT0354, MT0696. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 7 inches, mixed (Ap, Bk1 horizons); a calcic horizon from 6 to 61 inches (Bk1, Bk2, Bk3 horizons); a particle-size control section from 10 to 40 inches (Bk2, Bk3 horizons). Windham soils have a frigid temperature regime and an ustic moisture regime.