LOCATION BEEFTRAIL MTEstablished Series
TAXONOMIC CLASS: Sandy, mixed Ustic Haplocryolls
TYPICAL PEDON: Beeftrail coarse sandy loam in grassland (colors are for dry soil unless otherwise noted).
A1--0 to 3 inches; dark grayish brown (10YR 4/2) coarse sandy loam, very dark brown (10YR 2/2) moist; moderate medium granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and common fine and medium roots; 10 percent, mainly fine, gravel; moderately acid (pH 5.8); clear smooth boundary.
A2--3 to 8 inches; very dark grayish brown (10YR 3/2) coarse sandy loam, very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and few fine and medium roots; few very fine and fine tubular pores; 10 percent, mainly fine, gravel; slightly acid (pH 6.2); clear wavy boundary. (combined thickness of A horizons is 4 to 11 inches)
Bw--8 to 14 inches; brown (10YR 5/3) gravelly coarse sandy loam, brown (10YR 4/3) moist; moderate medium to coarse subangular blocky structure; slightly hard, very friable, slightly sticky and non-plastic; common very fine and few fine and medium roots; few very fine tubular pores; 20 percent, mainly fine, gravel; slightly acid (pH 6.4); gradual wavy boundary. (4 to 8 inches thick)
BC--14 to 26 inches; pale brown (10YR 6/3) gravelly loamy coarse sand, brown (10YR 5/3) moist; single grain; loose, non-sticky and non-plastic; few very fine roots; many very fine and common fine and medium interstitial pores; 30 percent, mainly fine, gravel; slightly acid (pH 6.4); clear wavy boundary. (8 to 22 inches thick)
Cr--26 to 35 inches; soft, weathered granite bedrock.
R--35 to 60 inches; hard granite bedrock.
TYPE LOCATION: Silver Bow County, Montana; 2,100 feet south and 1,150 feet east of the NW corner of sec. 11, T. 2 N., R. 8 W. Butte South topographic quadrangle, Latitude 45 degrees 56 minutes 23 seconds N. and Longitude 112 degrees 33 minutes 55 seconds W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature 38 to 42 degrees F., cryic temperature regime.
Soil moisture control section 12 to 35 inches or to the paralithic contact, whichever is shallower; dry in some or all parts for 90 or more cumulative days in normal years; not dry in all parts for more than half of the cumulative days when the soil temperature at a depth of 20 inches is higher than 43 degrees F. Ustic moisture regime.
Mollic epipedon thickness - 7 to 15 inches, mixed
Depth to sandy substrates - 8 to 18 inches
Depth to Cr horizon - 20 to 40 inches
Depth to R horizon 20 to 40 inches
These soils contain a high proportion of medium, coarse, and very coarse angular sand in the sand fraction inherant to granitic parent materials.
A Horizons Value: 3 or 4 dry; 2 or 3 moist
Chroma: 2 or 3
Texture: coarse sandy loam or sandy loam
Clay content: 10 to 18 percent
Rock fragment content: 5 to 30 percent--0 to 5 percent cobbles, 5 to 25 percent, mainly fine, gravel
Reaction: pH 5.6 to 6.8
Bw Horizon Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2, 3 or 4
Texture: Coarse sandy loam or sandy loam
Clay content: 8 to 18 percent
Rock fragment content: 15 to 35 percent--0 to 5 percent cobbles, 15 to 35 percent, mainly fine, gravel
Reaction: pH 6.2 to 7.0
BC Horizon Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3 or 4
Texture: loamy coarse sand or coarse sand
Clay content: 2 to 8 percent
Rock fragment content: 15 to 35 percent, mainly fine, gravel
Reaction: pH 6.4 to 7.2
COMPETING SERIES: These are the Bangston, Tomichi, and Wissikihon series. Bangston soils are very deep and lack appreciable medium, coarse and very coarse sand. Tomichi soils are very deep and lack a cambic horizon. Wissikihon soils are deep to a paralithic contact.
GEOGRAPHIC SETTING:
Landform- hillslopes, ridges, mountain flanks and bedrock floored pediments
Elevation - 5,220 to 7,610 feet
Slope - 2 to 50 percent
Parent material - residuum from granite or other coarse grained igneous or metamorphic rocks
Climate - long, cold winters; moist springs; cool, dry summers
Mean annual precipitation - 15 to 19 inches
Mean annual air temperature - 35 to 40 degrees F.
Frost-free period - 30 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Branham, Highrye and Zonite series. Branham soils are coarse loamy, having inherited a higher percentage of clay from the local geologic material. They occur on similar landscape positions. Zonite soils are very shallow to bedrock and occur on convex shoulder or nose slopes and ridges. Highrye soils are deeper that 40 inches to bedrock, are fine-loamy and have an argillic horizon. They occur in more depositional positions such as concave swales or footslopes.
DRAINAGE AND PERMEABILITY: somewhat excessively drained; rapid permeability over very slowly permeable granite bedrock.
USE AND VEGETATION: Beeftrail soils are primarily used for rangeland and wildlife habitat. The native vegetation is mainly bluebunch wheatgrass, Idaho fescue, rubber rabbitbrush, silvery lupine, needleandthread, fringed sagewort and other miscellaneous forbs and subshrubs.
DISTRIBUTION AND EXTENT: Beeftrail soils are of limited extent in foothills and mountains of southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Silver Bow County, Montana, 2006.
REMARKS: Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 8 inches (A1 and A2 horizons); a cambic horizon from 8 to 14 inches (Bw horizon); coarse sandy substrates below 14 inches (BC horizon); a paralithic contact at 26 inches (Cr horizon); a lithic contact at 35 inches (R horizon); a particle-size control section from 10 to 26 inches (Bw and BC horizons). Beeftrail soils have a cryic temperature regime and an ustic moisture regime. Gravel throughout the profile are primarily fine pea gravel less than 7 mm in diameter.