LOCATION DURREO COEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Haplocalcids
TYPICAL PEDON: Durreo gravelly fine sandy loam, 1 to 9 percent slopes, in rangeland; (colors are for dry soil unless otherwise noted)
A--0 to 15 centimeters; brown (7.5YR 5/3) gravelly fine sandy loam, dark brown (7.5YR 3/3) moist; 14 percent clay; weak fine granular structure; very friable, soft, nonsticky, nonplastic; common very fine and few fine roots throughout; common very fine vesicular pores; 20 percent gravel and 5 percent cobbles; slightly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (10 to 20 centimeters thick)
Bk1--15 to 36 centimeters; light brown (7.5YR 6/3) very cobbly fine sandy loam, brown (7.5YR 4/3) moist; 18 percent clay; weak fine subangular blocky structure; friable, slightly hard, slightly sticky, slightly plastic; common very fine and fine roots throughout; common very fine dendritic tubular pores; few irregular carbonate masses around rock fragments and common fine irregular carbonate masses on faces of peds; 25 percent gravel and 18 percent cobbles; strongly effervescent; 15 percent calcium carbonate equivalent; moderately alkaline (pH 8.4); clear wavy boundary. (13 to 51 centimeters thick)
Bk2--36 to 86 centimeters; pink (7.5YR 7/3) very cobbly fine sandy loam, brown (7.5YR 5/4) moist; 16 percent clay; weak medium subangular blocky structure; friable, slightly hard, slightly sticky, nonplastic; common very fine roots throughout; common very fine dendritic tubular pores; few irregular carbonate masses around rock fragments and many fine irregular carbonate masses in matrix; 25 percent gravel and 18 percent cobbles; violently effervescent; 26 percent calcium carbonate equivalent; strongly alkaline (pH 8.6); gradual wavy boundary. (25 to 89 centimeters thick)
Bk3--86 to 203 centimeters; pink (7.5YR 7/3) very cobbly fine sandy loam, brown (7.5YR 5/4) moist; 14 percent clay; weak medium subangular blocky structure; friable, slightly hard, slightly sticky, nonplastic; common very fine irregular pores; common irregular carbonate masses around rock fragments and many fine irregular carbonate masses in matrix; 25 percent gravel and 18 percent cobbles; violently effervescent; 40 percent calcium carbonate equivalent; strongly alkaline (pH 8.8).
TYPE LOCATION: Costilla County, USGS Blanca topographic quadrangle; 37 degrees 12 minutes 8.67 seconds north latitude and 105 degrees 35 minutes 40.60 seconds west longitude UTM 447,856 meters E, 4,124,013 meters N, zone 13; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture regime is typic aridic.
Mean annual soil temperature: 41 to 46 degrees F (5 to 7.8 degrees C)
Mean summer soil temperature: 59 to 63 degrees F (15 to 17.2 degrees degrees C)
Depth to calcic horizon: 4 to 8 inches (10 to 20 centimeters)
Particle-size control section (weighted average):
Clay content: 5 to 18 percent
Sand content: 52 to 70 percent
Rock fragments: 25 to 50 percent subangular gravel, 10 to 35 percent cobbles
A horizon:
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 2 or 3
Texture: gravelly fine sandy loam
Clay content: 5 to 18 percent
Carbonate clay content: 1 to 3 percent
Sand content: 60 to 75 percent
Silt content: 10 to 35 percent
Fragment content, total: 15 to 35 percent
Fragment size and content: 15 to 25 percent indurated basalt gravel
0 to 10 percent indurated basalt cobbles
Calcium carbonate equivalent: 0 to 5 percent
Electrical conductivity: 0 to 2 mmhos/cm
Sodium adsorption ratio: 0 to 1
Reaction: pH 7.4 to 8.4
Organic matter content: 1.0 to 2.0 percent
Bk horizon(s)
Hue: 7.5YR or 10YR
Value: 5 to 7 dry; 3 to 5 moist
Chroma: 3 or 4
Texture: very gravelly sandy loam, very cobbly sandy loam, very cobbly fine sandy loam, extremely cobbly sandy loam
Clay content: 5 to 18 percent
Carbonate clay content: 2 to 15 percent
Sand content: 52 to 75 percent
Silt content: 14 to 35 percent
Fragment content, total: 35 to 85 percent
Fragment size and content: 20 to 50 percent indurated basalt gravel
15 to 35 percent indurated basalt cobbles
Calcium carbonate equivalent: 15 to 45 percent
Electrical conductivity: 0 to 2 mmhos/cm
Sodium adsorption ratio: 0 to 1
Reaction: pH 7.8 to 9.0
Organic matter content: 0.0 to 1.0 percent
COMPETING SERIES:
Cambarge soils have a sandy-skeletal 2C horizon (lithologic discontinuity)
Garita soils have clay content between 18 and 35 percent in the particle size control section
Mitring soils are moderately deep to paralithic contact
Snowslide soils are moderately saline in the calcic horizon
GEOGRAPHIC SETTING:
Parent material: slope alluvium derived from basalt, andesite, and rhyolite
Landform: Volcanic hills
Slopes: 1 to 9 percent
Elevation: 7500 to 8000 feet
Mean annual air temperature: 41 to 46 degrees F (5 to 7.8 degrees C)
Mean annual precipitation: 6 to 8 inches (152 to 203 millimeters)
Precipitation pattern: Precipitation peaks in July and August occurring as intense summer thunderstorms.
Frost-free period: 85 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS:
Cososa soils are coarse-loamy.
Travelers soils are shallow to volcanic rock.
DRAINAGE AND PERMEABILITY: well-drained, low to medium runoff, moderately rapid permeability.
USE AND VEGETATION: These soils are used principally as rangeland. Typical vegetation is blue grama, foxtail, rabbitbrush, and winterfat.
DISTRIBUTION AND EXTENT: High intermountain valley of south central Colorado, LRR E, MLRA 51. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Costilla County, Costilla County soil survey area, Colorado, 2009. The name is coined.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 25 to 102 centimeters. (Bk horizons)
Ochric epipedon: The zone from 0 to 15 centimeters. (A horizons)
Calcic horizon: The zone from 15 to 203 centimeters. (Bk horizons)
The assignment of the cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.
Taxonomic Version: Tenth Edition, 2006