LOCATION BEANCREEK MT
Established Series
Rev. KTS-RJS
03/2012
BEANCREEK SERIES
The Beancreek series consists of very deep, well drained soils that formed in alluvium, colluvium or eolian deposits. Beancreek soils are on fan remnants, mountain slopes and dunes. Slopes range from 0 to 35 percent. Mean annual precipitation is about 430 mm and the mean annual temperature is about 3 degrees C.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Calcic Haplocryolls
TYPICAL PEDON: Beancreek fine sandy loam on a 2 percent slope in rangeland at about 2025 meters elevation. (Colors are for air-dry soil unless otherwise stated.)
A--0 to 12 cm; dark grayish brown (10YR 4/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium and fine granular structure; slightly hard, very friable, nonsticky and nonplastic; many very fine, fine, and medium roots; few very fine and fine tubular pores; trace of gravel; neutral (pH 7.0); clear smooth boundary. (10 to 20 cm thick)
Bw--12 to 31 cm; grayish brown (10YR 5/2) fine sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots; common very fine and fine irregular pores; trace of gravel; neutral (pH 7.2); gradual wavy boundary. (10 to 40 cm thick)
Bk1--31 to 56 cm; pale brown (10YR 6/3) fine sandy loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine irregular pores; trace of gravel; 22 percent soft masses of calcium carbonate and finely disseminated carbonates; violently effervescent; moderately alkaline (pH 8.2) gradual wavy boundary.
Bk2--56 to 76 cm; light gray (10YR 7/2) fine sandy loam, pale brown (10YR 6/3) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine irregular pores; trace of gravel; 8 percent soft masses of calcium carbonate and finely disseminated carbonates; violently effervescent; moderately alkaline (pH 8.4) gradual wavy boundary. (combined thickness of Bk horizons 40 to 125 cm thick)
C--76 to 152 cm; light brownish gray (10YR 6/2) loamy fine sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; trace of gravel; finely disseminated carbonates; strongly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Beaverhead County, Montana; located about 623 meters south and 651 meters east of the northwest corner of sec. 13, T. 14 S., R 5 W; Corral Creek topographic quadrangle; UTM 12T, 408023e., 4941166n. NAD 83.
RANGE IN CHARACTERISTICS:
Mean Annual Soil Temperature: 2 to 5 degrees C
Thickness of the Mollic epipedon: 18 to 40 cm
Depth to Calcic Horizon: 20 to 60 cm
Some pedons have a BC horizon
A horizon:
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 2 or 3; dry or moist
Clay content: 8 to 18 percent
Rock fragments: 0 to 15 percent gravel
Reaction: pH 6.8 to 7.6
Bw horizons:
Value: 4 to 6 dry; 2 or 3 moist
Chroma: 2 or 3; dry or moist
Texture: fine sandy loam, loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 20 percent gravel
Calcium Carbonate Equivalent: 0 to 5 percent
Reaction: pH 6.8 to 7.8
Bk horizons:
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 or 3; dry or moist
Texture: sandy loam, fine sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 15 percent gravel
Calcium Carbonate Equivalent: 15 to 35 percent
Reaction: pH 7.9 to 8.4
C horizon:
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 or 3; dry or moist
Texture: loamy fine sand, fine sandy loam
Clay content: 2 to 15 percent
Rock fragments: 0 to 15 percent gravel
Calcium Carbonate Equivalent: 3 to 15 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Ard (ID) - has a lithic contact at depths of less than 100 cm
Corralcreek (ID) - has a lithic contact at depths of less than 100 cm
Corralridge (ID) - has a xeric moisture regime
Parding (ID) - has a xeric moisture regime
GEOGRAPHIC SETTING:
Landform - fan remnants, mountain slopes, dunes
Elevation - 1,800 to 2,400 meters
Slope - 0 to 35 percent
Parent material- alluvium, colluvium or eolian deposits
Climate - long, cold winters; moist springs; short warm summers
Mean annual precipitation - 350 to 485 mm
Mean annual air temperature - 1 to 4 degrees C
Frost-free period - 50 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate rapid permeability.
USE AND VEGETATION: These soils are used mainly for rangeland. The vegetation is mainly bluebunch wheatgrass, Idaho fescue, POA (species), prairie junegrass, mountain big sagebrush, threetip sagebrush, grey horsebrush, rubber rabbitbrush, phlox, pussytoes, bluebells, lupine and other miscellaneous forbs.
DISTRIBUTION AND EXTENT: Beancreek soils are of minimal extent in southwest Montana. MLRA 43B and 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Horse Prairie-South Valley Area - Part of Beaverhead County, Montana, 2011; proposed in Beaverhead County, Montana, 2010.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from the surface to 31 cm. (A and Bw horizons)
Calcic Horizon - 31 to 76 cm (Bk horizon)
Particle-size control section - from 25 to 100 cm (part of the Bw, Bk1, Bk2 and part of the C horizons).
Beancreek soils have a cryic temperature regime and an ustic moisture regime.
Taxonomic version: Eleventh Edition, 2010.
National Cooperative Soil Survey
U.S.A.