LOCATION KEGSPRINGS MT
Established Series
REV. JJU-RJS
01/2012
KEGSPRINGS SERIES
The Kegsprings series consists of very deep, well drained soils that formed in colluvium derived from mixed igneous and interbedded, sedimentary rock. These soils occur on mountain slopes. Slopes are 8 to 50 percent. Mean annual precipitation is about 760 mm and the mean annual air temperature is about 3 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Haplocryepts
TYPICAL PEDON: Kegsprings very gravelly loam, forested. This profile was described on a 32 percent slope at an elevation of 2412 meters (colors are for dry soil unless otherwise noted).
Oi--0 to 9 cm; slightly decomposed forest litter; clear smooth boundary. (4 to 10 cm thick)
A--9 to 22 cm; dark grayish brown (10YR 4/2) very gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine, fine, medium and coarse roots; many very fine and fine irregular pores; 35 percent gravel; slightly acid (pH 6.2); clear smooth boundary. (9 to 20 cm thick)
Bw1--22 to 62 cm; brown (10YR 4/3) very gravelly loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, fine and medium roots; many very fine and fine irregular pores; 45 percent gravel; moderately acid (pH 6.0); clear wavy boundary.
Bw2--62 to 94 cm; grayish brown (10YR 5/2) very gravelly sandy clay loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and moderately plastic; common very fine and fine roots; common fine tubular pores; 50 percent gravel; moderately acid (pH 6.0); clear wavy boundary. (combined thickness of Bw horizons - 60 to 80 cm thick)
BC--94 to 152 cm; brown (10YR 5/3) very gravelly sandy clay loam, grayish brown (10YR 5/2) moist; weak fine subangular blocky; soft, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common fine tubular pores; 55 percent gravel; slightly acid (pH 6.2).
TYPE LOCATION: Beaverhead County, Montana; located about 235 meters south and 293 meters east of the northwest corner of sec. 14, T. 14N., R 2W; Slide Mountain topographic quadrangle; UTM 12T, 435022e, 4931262n, NAD 83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 2 to 5 degrees C.
Depth to top of cambic horizon - 13 to 30 cm
Particle-size control section - averages 18 to 27 percent clay
A horizon
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2 or 3; dry or moist
Clay content: 18 to 27 percent
Rock fragments: 35 to 50 percent gravel
Reaction: pH 5.6 to 6.4
Bw horizons
Value: 4 to 6; dry or moist
Chroma: 2 or 3; dry or moist
Texture: loam or sandy clay loam
Clay content: 18 to 27 percent
Rock fragments: 35 to 55 percent gravel
Reaction: pH 5.6 to 6.4
BC horizon
Value: 4 to 6; dry or moist
Chroma: 3 or 4 dry; 2 to 4 moist
Texture: loam or sandy clay loam
Rock fragments: 35 to 60 percent gravel
Clay content: 18 to 27 percent
Reaction: pH 5.6 to 6.4
COMPETING SERIES:
Basaltlake (AK) - have a buried A horizon
Butchlake (AK) - have a lithologic discontinuity
Cuberant (UT) - have a lithic contact at depths of less than 100 cm
Enentah (CO) - have an accumulation of sesquioxides
Garlet (MT) - have secondary calcium carbonate accumulation
Gromes (NM) - does not have sandy clay loam textures in control section
Holokukfamily (AK) - have a lithologic discontinuity
Mountedith (MT) - have an E horizon
Soakpak (AK) - have a lithologic discontinuity
Storm (CO) - have an E horizon
Targhee (ID) - have a lithic contact at depths of less than 100 cm
Telay (AK) - have a lithologic discontinuity
GEOGRAPHIC SETTING:
Landform - mountain slopes
Elevation - 2130 to 2750 meters
Slope - 8 to 50 percent
Parent material - colluvium from mixed igneous and interbedded, sedimentary rock
Climate - long, cold winters; moist springs; short warm summers.
Mean annual precipitation - 600 to 1020 mm
Mean annual air temperature - 1 to 4 degrees C.
Frost-free period - 30 to 50 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Kegsprings soils are used mainly for understory grazing and timber. The vegetation is mainly Douglas-fir, subalpine fir, lodgepole pine, snowberry, buffaloberry, heartleaf arnica, pinegrass, and other miscellaneous grasses and forbs.
DISTRIBUTION AND EXTENT: Kegsprings soils are of small extent in southwestern Montana. MLRA - 43B.
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:
Ochric epipedon - from 0 to 22 cm (Oi and A horizons)
Cambic horizon - from 22 to 94 cm (Bw1 and Bw2 horizons)
Particle-size control section - from 34 to 109 cm (Bw1, Bw2 and part of the BC horizons)
Kegsprings soils have a cryic temperature regime and an udic moisture regime.
Taxonomic version: Eleventh Edition, 2010.
National Cooperative Soil Survey
U.S.A.