LOCATION CALPET WY
Tentative Series
Rev. TAG-DMM-RJS
05/2011
CALPET SERIES
The Calpet series consists of very deep, well drained soils that formed in slope alluvium or colluvium derived from metamorphic and sedimentary rock. These soils are on escarpments and mountain slopes. Slopes are 8 to 50 percent. Mean annual precipitation is 430 mm and mean annual air temperature is about 1 degree C.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Ustic Haplocryalfs
TYPICAL PEDON: Calpet loam, in rangeland (colors are for dry soil unless otherwise noted).
A--0 to 7 cm; brown (7.5YR 4/2) loam, dark brown (7.5YR 3/2) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine, and common medium and coarse roots; many fine interstitial pores; 10 percent gravel; slightly effervescent; slightly alkaline (pH 7.6); clear smooth boundary. (5 to 20 cm thick)
Btk1--7 to 26 cm; brown (7.5YR 5/4) gravelly loam, brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; moderately hard, firm, slightly sticky and slightly plastic; many very fine and fine, and common medium and coarse roots; many fine interstitial pores; 20 percent continuous distinct clay films on all faces of peds; 35 percent continuous prominent calcium carbonate coats on bottom surfaces of rock fragments; 25 percent gravel; strongly effervescent; slightly alkaline (pH 7.7); clear smooth boundary. (15 to 35 cm thick)
Btk2--26 to 68 cm; yellowish red (5YR 5/6) very gravelly clay loam, yellowish red (5YR 4/6) moist; moderate medium subangular blocky structure; hard, very firm, moderately sticky and moderately plastic; common very fine and fine, and few medium and coarse roots; many fine interstitial pores; 45 percent continuous distinct clay films on all faces of peds; 45 percent continuous prominent calcium carbonate coats on bottom surfaces of rock fragments, 2 percent calcium carbonate masses in matrix, and finely disseminated calcium carbonate in matrix; 30 percent gravel, 10 percent cobbles; violently effervescent; moderately alkaline (pH 8.1); gradual wavy boundary. (30 to 50 cm thick)
Bk--68 to 200 cm; reddish brown (5YR 5/4) very gravelly loam, reddish brown (5YR 4/4) moist; moderate medium subangular blocky structure; moderately hard, firm, slightly sticky and slightly plastic; common very fine and fine, and few medium roots; many fine interstitial pores; 55 percent continuous prominent calcium carbonate coats on bottom surfaces of rock fragments, 4 percent calcium carbonate masses in matrix, and finely disseminated calcium carbonate in matrix; 30 percent gravel, 10 percent cobbles; violently effervescent; strongly alkaline (pH 8.5).
TYPE LOCATION: Sublette County, Wyoming; located approximately 730 feet south and 2,100 feet east from the NW corner of section 27, T. 29N, R. 114W; USGS Pine Grove Ridge, Wyoming topographic quadrangle; 42 degrees 28 minutes 33.00 seconds north latitude and 110 degrees 24 minutes 31.00 seconds west longitude.
RANGE IN CHARACTERISTICS:
Soil temperature - 1.5 to 4.0 degrees C.
Depth to top of argillic horizon - 5 to 20 cm
Depth to secondary calcium carbonate accumulation - 5 to 20 cm
Particle-size control section (weighted average) - less than 35 percent rock fragments
A horizon
Hue: 7.5YR or 5YR; dry or moist
Value: 3 or 4 dry; 2 or 3 moist
Chroma: 2 or 3; dry or moist
Clay content: 15 to 26 percent
Rock fragments: 5 to 15 percent gravel
Calcium carbonate equivalent: 1 to 3 percent
Reaction: pH 7.4 to 7.8
Btk1 horizon
Hue: 7.5YR or 5YR; dry or moist
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 4 or 6; dry or moist
Texture: clay loam, loam, sandy clay loam
Clay content: 19 to 35 percent
Carbonate clay content: 0 to 4 percent
Rock fragments: 15 to 25 percent--15 to 25 percent gravel, 0 to 5 percent cobbles
Calcium carbonate equivalent: 1 to 15 percent
Reaction: pH 7.6 to 8.2
Btk2 horizon
Hue: 2.5YR or 5YR; dry or moist
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 4 or 6; dry or moist
Texture: clay loam, loam, sandy clay loam
Clay content: 19 to 35 percent
Carbonate clay content: 0 to 4 percent
Rock fragments: 25 to 45 percent--20 to 35 percent gravel, 0 to 10 percent cobbles
Calcium carbonate equivalent: 1 to 15 percent
Reaction: pH 7.6 to 8.2
Bk horizon
Hue: 2.5YR or 5YR; dry or moist
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 4 or 6; dry or moist
Texture: loam, clay loam, sandy clay loam
Clay content: 20 to 35 percent
Rock fragments content: 15 to 45 percent--15 to 35 percent gravel, 0 to 10 percent cobbles
Calcium carbonate equivalent: 5 to 15 percent
Sodium adsorption ratio: 0 to 7
Reaction: pH 7.9 to 8.6
COMPETING SERIES:
Ansel (WY) - does not have secondary calcium carbonate accumulation
Howlett (CO) - does not have secondary calcium carbonate accumulation
Weminuche (CO) - does not have secondary calcium carbonate accumulation
Wix (CO) - are moderately deep to a paralithic contact
GEOGRAPHIC SETTING:
Landform - escarpments, mountain slopes
Elevation - 2240 to 2835 meters
Slope - 8 to 50 percent
Parent Material - slope alluvium or colluvium derived from metamorphic and sedimentary rock
Climate - long, cold winters; cool, moist springs; short, cool summers
Mean annual precipitation - 400 to 610 mm with peak periods of precipitation occurring during the spring
Mean annual air temperature - 0.5 to 2.5 degrees C.
Frost-free period - 15 to 40 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Calpet soils are primarily used for rangeland. The potential native vegetation is mainly mountain big sagebrush, Letterman's needlegrass, Columbia needlegrass, snowberry and Idaho fescue.
DISTRIBUTION AND EXTENT: Calpet soils are of small extent in southwestern Wyoming. MLRA - 43B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES PROPOSED: Sublette County, Wyoming, 2011. The series name is derived from a local landmark.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 7 cm (A horizon)
Argillic horizon - from 7 to 68 cm (Btk1, Btk2 horizons)
Secondary calcium carbonate accumulation - from 7 to 200 cm (Btk1, Btk2, Bk horizons)
Particle-size control section - from 7 to 57 cm (Btk1, part of Btk2 horizons).
Calpet soils have a cryic temperature regime and an ustic moisture regime.
Taxonomic version: Eleventh Edition, 2010.
National Cooperative Soil Survey
U.S.A.