LOCATION FOXTON             WY
Established Series
Rev. JN-JAL
11/2005

FOXTON SERIES


The Foxton series consists of moderately deep, well drained soils that formed in alluvium or residuum derived from interbedded limestone and shale. These soils are on mountain slopes of 2 to 20 percent. The mean annual temperature is about 36 degrees F.

TAXONOMIC CLASS: Fine, smectitic Eutric Haplocryalfs

TYPICAL PEDON: Foxton loam-on an 11 percent concave, north-facing slope under lodgepole pine and Engelmann spruce. When described, the soil was moist throughout. (Colors are for moist soil unless otherwise stated.)

Oi--0 to 3 inches; partially decomposed organic materials.

E--3 to 8 inches; dark grayish brown (10YR 4/2) loam, light brownish gray (10YR 6/2) dry; moderate thin platy and moderate medium subangular blocky structure; friable, slightly sticky and slightly plastic; 5 percent gravel; slightly acid (pH 6.2); clear wavy boundary. (3 to 6 inches thick)

Btl--8 to 16 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 5/4) dry; moderate medium and fine prismatic structure parting to strong medium angular blocky; very firm, very sticky and very plastic; continuous prominent clay films on faces of peds; 10 percent gravel; slightly acid (pH 6.4); clear wavy boundary.

Bt2--16 to 29 inches; reddish brown (5YR 4/4) cobbly clay, reddish brown (5YR 5/4) dry; moderate coarse angular blocky structure; very firm, very sticky and very plastic; common distinct clay films on faces of peds; 15 percent gravel and 15 percent cobbles; slightly alkaline (pH 7.4); clear wavy boundary. (The combined thickness of the Bt horizons is 17 to 34 inches.)

R--29 inches; limestone bedrock.

TYPE LOCATION: Sheridan County, Wyoming; center of SW1/4 of sec. 14, T. 56 N., R. 89 W.

RANGE IN CHARACTERISTICS: The thickness of the solum and depth to bedrock typically are about 26 inches but range from 20 to 40 inches. Some pedons have thin, dark colored A horizons with 1 to 4 percent organic matter. Average cation exchange capacity to the base of the argillic horizon ranges from 60 to 100 millequivalents per 100 grams of soil. The mean annual soil temperature ranges from 32 to 44 degrees F. Rock fragment content ranges from none in the upper part of the solum to a maximum of 35 percent in the lower part of the solum directly above the lithic contact. The soils are typically noncalcareous throughout but may be slightly effervescent near the coarse fragments immediately above the bedrock.

The A horizon, if present, is thin, less than three inches thick, and has a hue of 10YR or 7.5YR, value of 3 through 5 dry, 2 through 4 moist, and chroma of 1 or 2. It is slightly acid or neutral.

The E horizon has hue of 10YR or 7.5YR, value of 5 or 6 dry, 4 or 5 moist, and chroma of 2 through 4. It is commonly loam, fine sandy loam, or very fine sandy loam and less commonly silt loam, sandy clay loam, or clay loam. Rock fragments range from 0 to 10 percent and are 0 to 10 percent gravel and 0 to 25 percent cobbles. It is moderately acid to neutral.

The Bt horizon has hue of 10YR through 2.5YR, value of 4 through 6 dry, 3 or 4 moist, and chroma of 3 through 6. It is commonly clay in the upper part and cobbly clay in the lower part and less commonly silty clay loam or clay loam which may be modified with coarse fragments. The Bt horizon is 35 to 50 percent clay and contains less than 40 percent fine sand or coarser. Rock fragments are gravel or cobbles and range from 5 to 20 percent gravel and 0 to 20 percent cobbles. It is slightly acid to slightly alkaline.

The BC horizon, if present, has the same color range as the Bt horizon. It is cobbly clay loam or cobbly silty clay loam. It is neutral or slightly alkaline.

The lithic contact is commonly composed of Amsden limestone but because of interbedding is less commonly hard sandstone or shale.

COMPETING SERIES: These are the Mikesell and Owlcan series. Mikesell and Owlcan soils lack a lithic contact above 40 inches.

GEOGRAPHIC SETTING: Foxton soils are on mountain slopes that have a plain or concave surface. The slope gradient commonly is 3 to 12 percent, but the range is 2 to 20 percent. The soils formed in fine textured alluvium or residuum of weathered limestone interbedded with thin lenses of sandstone and shale. The mean annual temperature varies from 34 to 38 degrees F., and the mean annual precipitation is 20 to 36 inches. Elevations range from 6,500 to over 9,000 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bottle, Cloud Peak, and Sapphire soils at the type location. The Bottle soils have sandy sola and are on steeper slopes. Cloud Peak soils have loamy-skeletal argillic horizons, and Sapphire soils have fine-loamy argillic horizons. They occur on the steeper and more convex parts of the mountain slopes.

DRAINAGE AND PERMEABILITY: Well drained; runoff is medium; permeability is slow.

USE AND VEGETATION: These soils are used for forestry, limited livestock grazing, and recreation. Native vegetation is typically lodgepole pine with mixes of Engelmann spruce and alpine fir.

DISTRIBUTION AND EXTENT: Mountains of Wyoming and northern Colorado. Foxton soils are moderately extensive.

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

SERIES ESTABLISHED: Sheridan County, Wyoming; 1982. Big Horn National Forest, parts of Sheridan, Johnson, Big Horn, and Washakie Counties, Wyoming.


National Cooperative Soil Survey
U.S.A.