LOCATION WINDLASS                MT

Established Series
Rev. ADI-JJU-RJS
09/2011

WINDLASS SERIES

The Windlass series consists of very deep, somewhat poorly drained soils that formed in loamy alluvium over sand and gravel. These soils are on outwash plains, alluvial fans, flood plains and stream terraces. Slopes are 0 to 4 percent. Mean annual precipitation is about 17 inches, and mean annual air temperature is about 42 degrees F.

TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Oxyaquic Haplustolls

TYPICAL PEDON: Windlass loam, in pasture (colors are for dry soil unless otherwise noted).

Ap--0 to 10 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; common very fine and fine pores; neutral (pH 7.2); clear smooth boundary. (7 to 13 inches thick)

Bw--10 to 14 inches; brown (10YR 5/3) fine sandy loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; common fine and medium, and many very fine tubular pores; neutral (pH 7.0); clear wavy boundary. (4 to 10 inches thick)

2C1--14 to 19 inches; brown (10YR 5/3) very gravelly loamy sand, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; soft, friable, nonsticky and nonplastic; many very fine and fine roots; common fine and very fine tubular pores; 25 percent gravel and 10 percent cobbles; neutral (pH 7.0); gradual smooth boundary. (0 to 5 inches thick)

2C2--19 to 60 inches; pale brown (10YR 6/3) very gravelly sand, brown (10YR 5/3) moist; few fine prominent brownish yellow (10YR 6/8) and yellowish brown (10YR 5/8) moist redox concentrations; single grain; loose; nonsticky and nonplastic; common very fine and fine roots; 30 percent gravel and 20 percent cobbles; neutral (pH 7.0).

TYPE LOCATION: Granite County, Montana; 1,200 feet west and 1,400 feet south of the northeast corner of sec. 24, T. 5N, R. 16W.

RANGE IN CHARACTERISTICS:
Soil temperature - 41 to 46 degrees F.
Mollic epipedon thickness - 7 to 15 inches
Depth to seasonal high water table - 24 to 42 inches
Depth to lithologic discontinuity - 12 to 20 inches

Note: Some pedons may have an Oi horizon -- 1 to 3 inches thick

Ap horizon
Value: 2 or 3; moist
Chroma: 1 or 2; dry or moist
Clay content: 15 to 25 percent
Rock fragments: 0 to 15 percent--0 to 10 percent gravel, 0 to 5 percent cobbles
Reaction: pH 6.6 to 7.8

Bw horizon
Value: 4 to 6 dry; 3 or 4 moist
Chroma: 2 or 3; dry or moist
Texture: loam, sandy loam or fine sandy loam
Clay content: 18 to 27 percent
Rock fragments: 0 to 15 percent--0 to 10 percent gravel, 0 to 5 percent cobbles
Reaction: pH 6.6 to 7.8

2C1 horizon
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 to 4; dry or moist
Texture: sandy loam, loamy sand or loam
Clay content: 5 to 18 percent
Rock fragments: 35 to 60 percent--25 to 40 percent gravel, 10 to 20 percent cobbles
Calcium carbonate equivalent: 0 to 3 percent
Reaction: pH 6.6 to 7.8

2C2 horizon
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 or 3; dry or moist
Texture: loamy sand or sand
Clay content: 2 to 12 percent
Rock fragments: 40 to 70 percent--25 to 50 percent gravel, 15 to 25 percent cobbles
Calcium carbonate equivalent: 0 to 3 percent
Reaction: pH 6.6 to 7.8

COMPETING SERIES:
Carten (MT) - have a secondary calcium carbonate accumulation

GEOGRAPHIC SETTING:
Landform - outwash plains, alluvial fans, flood plains and stream terraces
Elevation - 3,600 to 6,200 feet
Slope - 0 to 4 percent
Parent material - loamy alluvium over sand and gravel
Climate - long, cold winters; moist springs; warm summers
Mean annual precipitation - 9 to 19 inches
Mean annual air temperature - 39 to 44 degrees F.
Frost-free period - 70 to 105 days

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Nirling and Bandy soils. The Nirling soils are sandy-skeletal. The Bandy soils are coarse-loamy over sandy or sandy-skeletal and less than 24 inches to a seasonally high water table. These soils occur on similar landforms as the Windlass soils.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderate permeability in the fine-loamy material and rapid in the sandy-skeletal material.

USE AND VEGETATION: Windlass soils are used mainly for pastureland and hayland. Potential native vegetation is mainly tall reedgrass, tufted hairgrass, prairie cordgrass, basin wildrye, and Nebraska sedge.

DISTRIBUTION AND EXTENT: Windlass soils are of small extent in mountain valleys of western Montana. MLRA - 44B.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.

SERIES ESTABLISHED: Granite County Area, Montana, 1996.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 14 inches (Ap, Bw horizons)
Lithologic discontinuity - at 14 inches (2C1 horizion)
Particle-size control section - from 10 to 40 inches (Bw, 2C1, part of 2C2 horizons)

Windlass soils have a frigid temperature regime, an ustic moisture regime, and an oxyaquic moisture subclass.

ADDITIONAL DATA: Soil interpretations record - MT1484.

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National Cooperative Soil Survey
U.S.A.