LOCATION KELLYCREEK MT
Established Series
Rev. JJU-RJS
01/2012
KELLYCREEK SERIES
The Kellycreek series consists of moderately deep, somewhat excessively drained soils that formed in colluvium over residuum weathered from red, calcareous conglomerate or other red sedimentary rock. These soils occur on hills, escarpments and eroded fan remnants. Slopes range from 4 to 50 percent. Mean annual precipitation is about 305 mm, and the mean annual air temperature is about 5 degrees C.
TAXONOMIC CLASS: Sandy-skeletal, mixed, frigid Aridic Calciustepts
TYPICAL PEDON: Kellycreek gravelly sandy loam, in rangeland (colors are for dry soil unless otherwise noted).
A--0 to 13 cm; reddish brown (5YR 5/4) gravelly sandy loam, dark reddish gray (5YR 4/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many fine irregular pores; 15 percent gravel, 10 percent cobbles; finely disseminated calcium carbonate; strongly effervescent; moderately alkaline (pH 8.0); clear smooth boundary. (5 to 15 cm thick)
Bk1--13 to 46 cm; light reddish brown (5YR 6/3) gravelly sandy loam, reddish brown (5YR 5/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine roots; many fine irregular pores; 25 percent gravel, 5 percent cobbles; 3 percent fine soft masses of calcium carbonate, 50 percent distinct calcium carbonate coats on rock fragments; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (20 to 40 cm thick)
Bk2--46 to 84 cm; light reddish brown (5YR 6/4) extremely gravelly loamy sand, reddish brown (5YR 5/4) moist; weak very fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine roots; many very fine interstitial pores; 60 percent gravel, 5 percent cobbles; 10 percent fine soft masses of calcium carbonate, 50 percent distinct calcium carbonate coats on rock fragments; violently effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (25 to 50 cm thick)
BCk--84 to 97 cm; light reddish brown (2.5YR 6/4) very gravelly loamy sand, reddish brown (2.5YR 5/4) moist; single grained; loose, nonsticky and nonplastic; few very fine roots; common very fine interstitial pores; 45 percent gravel; finely disseminated calcium carbonate, 50 percent distinct calcium carbonate coats on rock fragments; strongly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (10 to 35 cm thick)
Cr--97 to 152 cm; red (10R 5/6) calcareous moderately cemented conglomerate bedrock that crushes to loamy sand.
TYPE LOCATION: Beaverhead County, Montana; Dalys topographic quadrangle. UTM 12T, 0355721e, 4996870n, NAD83; 2500 feet west and 1800 feet south of the NE corner of sec.28 , T.20 N., R 10 W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 5 to 7 degrees C.
Depth to a calcic horizon: 10 to 25 cm
Depth to a paralithic contact: 50 to 100 cm
Note: Some pedons may have a lithic contact below 100 cm.
A horizon
Hue: 7.5YR, 5YR or 2.5YR; dry or moist
Value: 4 or 5; dry or moist
Chroma: 2 to 4; dry or moist
Texture: sandy loam
Clay content: 10 to 18 percent
Rock fragments: 15 to 35 percent--10 to 35 percent gravel, 0 to 15 percent cobbles
Calcium carbonate equivalent: 1 to 5 percent
Reaction: pH 7.6 to 8.2
Bk1 horizon
Hue: 7.5YR, 5YR or 2.5YR; dry or moist
Value: 5 to 8 dry; 3 or 5 moist
Chroma: 2 to 3; dry or moist
Texture: loamy sand or sandy loam
Clay content: 5 to 15 percent
Rock fragments: 35 to 65 percent--20 to 50 percent gravel, 0 to 20 percent cobbles and stones
Calcium carbonate equivalent: 10 to 35 percent
Reaction: pH 7.9 to 8.4
Bk2 horizon
Hue: 7.5YR, 5YR or 2.5YR; dry or moist
Value: 5 to 8 dry; 3 or 5 moist
Chroma: 2 to 4; dry or moist
Texture: loamy sand or sand
Clay content: 1 to 12 percent
Rock fragments: 35 to 70 percent--30 to 60 percent gravel, 0 to 25 percent cobbles and stones
Calcium carbonate equivalent: 15 to 35 percent
Reaction: pH 7.9 to 8.4
BCk horizon
Hue 5YR, 2.5YR or 10R; dry or moist
Value: 5 to 8 dry; 4 through 7 moist
Chroma: 3 to 6; dry or moist
Texture: loamy sand or sand
Clay content: 1 to 12 percent
Rock fragments: 35 to 65 percent--25 to 50 percent gravel, 0 to 25 percent cobbles
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Scravo (MT) - is very deep.
GEOGRAPHIC SETTING:
Landform - hills, escarpments and eroded fan remnants
Elevation - 1675 to 2075 meters
Slope - 4 to 50 percent
Parent Material - colluvium over residuum weathered from red, calcareous conglomerate or other red sedimentary rock
Climate - long, cold winters; moist springs; short summers
Mean annual precipitation - 250 to 360 mm
Mean annual temperature - 4 to 7 degrees C.
Frost-free period - 70 to 90 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; rapid permeability.
USE AND VEGETATION: Kellycreek soils are used as native rangeland. Native vegetation is mainly mountain grasses and forbs dominated by bluebunch wheatgrass, needleandthread, western wheatgrass, prairie junegrass, prickly pear cactus and big sagebrush.
DISTRIBUTION AND EXTENT: Southwest Montana. The series is of small extent. 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, 2008.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - 0 to 13 cm (A horizon)
Calcic horizon - 13 to 97 cm (Bk1, Bk2, BCk horizons)
Particle size control section from 25 to 97 cm (part of Bk1, Bk2, BCk horizons)
Kellycreek soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.
National Cooperative Soil Survey
U.S.A.