LOCATION YANKEEBOY COEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, shallow Typic Haplocryolls
TYPICAL PEDON: Yankeeboy clay loam, on a north facing 47 percent mountain slope on rangeland at an elevation of 9,680 feet. (colors are for dry soil unless otherwise noted. When described on September 26, 1985, the soil was moist throughout.)
A--0 to 11 inches; dark grayish brown (10YR 4/2) clay loam, very dark brown (10YR 2/2) moist; moderate fine and medium granular structure; hard, firm, sticky and plastic; 5 percent shale chips; neutral (pH 7.2); abrupt smooth boundary. (7 to 15 inches thick)
Cr--11 inches; weathered shale bedrock.
TYPE LOCATION: San Miguel County, Colorado; about 8 miles southwest of Placerville, Colorado; located about 200 feet east and 600 feet north of the southwest corner of Section 15, T. 42 N., R. 11 W.; USGS Little Cone topographic quadrangle; latitude 37 degrees, 53 minutes, 52 seconds north and longitude 108 degrees, 04 minutes, 29 seconds west, NAD 1927.
RANGE IN CHARACTERISTICS:
Soil moisture regime: udic; dry for less than 30 days in summer
Mean annual soil temperature: 37 to 43 degrees F.
Depth to paralithic contact: 10 to 20 inches
Thickness of mollic epipedon: 7 to 15 inches.
Particle-size control section:
Clay content: 35 to 50 percent
Rock fragment content: 0 to 10 percent
A horizon:
Hue: 10YR or 2.5Y
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1 to 3 dry or moist
Rock fragments: shale. 0 to 10 percent total rock fragments; 0 to 10 percent gravel, mostly as chips or small channers.
Some pedons may have a Bw or C horizon.
COMPETING SERIES: This is the Doby series. The Doby soils have an ustic moisture regime (assumed from its vegetation and precipitation).
GEOGRAPHIC SETTING: The Yankeeboy soils formed in slope alluvium and colluvium over residuum derived from shale on mountain slopes and ridges . Slopes range from 15 to 65 percent. Elevation ranges from 9,400 to 10,800 feet. The mean annual temperature is about 33 to 39 degrees F. The mean annual precipitation is about 27 to 33 inches. The frost-free period is 50 to 65 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lizardhead and Mountpoor soils. Lizardhead soils are on backslopes and summits and are deeper than 60 inches. Mountpoor soils are on backslopes and footslopes and are deeper than 60 inches.
DRAINAGE AND PERMEABILITY: well drained; very high runoff; slow permeability.
USE AND VEGETATION: This soil is used for rangeland. Potential native vegetation is shrubby cinquefoil, slender wheatgrass, Thurber fescue, and nodding bromegrass. It is in the Subalpine Clay Range Site, RS 252.
DISTRIBUTION AND EXTENT: Western Colorado in LRR E and MLRA 48A. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Ouray Soil Survey Area, Uncompahgre National Forest, San Miguel County, Colorado, 1998. The name comes from Yankee Boy Basin near Ouray, Colorado.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon: the zone from 0 to 11 inches. (A horizon)
Paralithic contact: weathered shale bedrock at 11 inches. (Cr layer)
Particle-size control section: the zone from 0 to 11 inches (A horizon)
This pedon was classified in accordance with Keys to Soil Taxonomy, 7th Edition, 1996.