LOCATION CORPEN COEstablished Series
TAXONOMIC CLASS: Loamy, micaceous, frigid Lithic Calciustolls
TYPICAL PEDON: Corpen gravelly sandy loam, on a west facing, 9 percent slope in grassland at an elevation of 7,750 feet. (Colors are for dry soil unless otherwise noted)
A--0 to 4 inches; brown (10YR 4/3) gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak thin platy structure; soft, very friable, slightly sticky and nonplastic; many very fine and fine roots; few very fine and fine pores; 25 percent gravel, 4 percent cobbles; neutral (pH 7.0); abrupt smooth boundary. (3 to 5 inches thick)
Ak--4 to 9 inches; dark grayish brown (10YR 4/2) gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few very fine and fine roots; few very fine and fine pores; strongly effervescent; few fine calcium carbonate masses; 6 percent calcium carbonate equivalent; 30 percent gravel; slightly alkaline (pH 7.8); abrupt wavy boundary. (4 to 6 inches thick)
Bk--9 to 14 inches; light gray (10YR 7/2) gravelly sandy loam, pale brown (10YR 6/3) moist; massive; soft, very friable, slightly sticky and nonplastic; few very fine and fine roots; few very fine and fine pores; violently effervescent; many coarse calcium carbonate masses; 9 percent calcium carbonate equivalent; 30 percent gravel; moderately alkaline (pH 8.3); abrupt irregular boundary. (5 to 8 inches thick)
R--14 to 60 inches; indurated gneiss.
TYPE LOCATION: Teller County, Colorado; about 6 miles southwest of Cripple Creek; about 400 feet south and 1,700 feet east of the northwest corner of sec. 31, T. 15 S., R. 70 W.; High Park USGS quad; lat. 38 degrees 42 minutes 39 seconds and long. 105 degrees 16 minutes 17 seconds, NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is usually dry in some part in early summer, moist in some or all parts in late July and August, and intermittently dry in fall; ustic regime, typic subclass.
Mean annual soil temperature: 44 to 46 degrees F.
Mean summer soil temperature: 59 to 65 degrees F.
Thickness of mollic epepedon: 7 to 11 inches
Depth to calcic horizon: 4 to 7 inches
Depth to lithic contact: 10 to 20 inches
Lithology of rock fragments: gneiss
Particle-size control section (weighted average):
Noncarbonate clay content: 10 to 18 percent
Rock fragments: 15 to 35 percent gravel
Mica content (grain count): 45 to 55 percent (estimated)
A horizon:
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 2 or 3 dry, 1 or 2 moist
Texture: gravelly loam, gravelly sandy loam
Clay content: 10 to 18 percent
Gravel content: 15 to 30 percent
Cobble content: 0 to 5 percent
Reaction: neutral or slightly alkaline
Ak horizon:
Hue: 10YR or 7.5YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3 dry, 1 or 2 moist
Texture: gravelly loam, gravelly sandy loam
Clay content: 10 to 18 percent
Gravel content: 15 to 35 percent
Calcium carbonate equivalent: 5 to 10 percent
Reaction: slightly alkaline or moderately alkaline
Bk horizon:
Hue: 10YR or 7.5YR
Value: 5 through 7 dry, 4 through 6 moist
Chroma: 2 through 4 dry, 2 through 6 moist
Texture: gravelly loam, gravelly sandy loam
Clay content: 10 to 18 percent
Gravel content: 15 to 35 percent
Calcium carbonate equivalent: 5 to 10 percent
Reaction: moderately alkaline or strongly alkaline
COMPETING SERIES:
There are no competing series in this family. A soil in a closely related family is the
Corpening series. Corpening soils have rock fragments of limestone.
GEOGRAPHIC SETTING:
Parent material: slope alluvium derived from gneiss
Landform: pediments
Slopes: 5 to 25 percent
Elevation: 6,700 to 8,600 feet
Mean annual air temperature: 42 to 44 degrees F.
Mean annual precipitation: 14 to 16 inches
Precipitation pattern: Monthly precipitation is lowest in winter and greatest in July and August.
Frost-free period: 80 to 100 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cathedral and Howbert series. The Cathedral soils do not have a secondary carbonates. The Howbert soils are are very deep.
DRAINAGE AND PERMEABILITY: Well drained, moderately rapid permeability.
USE AND VEGETATION: These soils are used mainly for livestock grazing and wildlife habitat. Potential native vegetation is mainly blue grama, Arizona fescue, Parry's oatgrass, green needlegrass, big bluestem, western wheatgrass, and mountain muhly.
DISTRIBUTION AND EXTENT: Central Colorado; LRR E, MLRA 48A; small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Teller County, Colorado, Teller-Park soil survey area, 2004. The name is coined.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Series control section: 0 to 14 inches
Particle-size control section: The zone from 0 to 14 inches. (A, Ak, Bk horizons)
Mollic epipedon: The zone 0 to 9 inches. (A, Ak horizons)
Calcic horizon: The zone from 4 to 14 inches. (Ak and Bk horizons)
Lithic contact: The contact with gneiss at 14 inches. (R layer)
Frigid temperature regime.
The 08/2010 revision updated the classification from paramicaceous to micaceous.
Taxonomic Version: Eleventh Edition, 2010