LOCATION TELLURIDE CO
Established Series
Rev. JPP/TWH/KLS
03/2018
TELLURIDE SERIES
The Telluride series consist of shallow, well drained soils formed in slope alluvium or colluvium over residuum and till derived from andesite, rhyolite, breccia, basalt, or tuff. These soils are on basin floors, ridges, mountain slopes, hillslopes, and mesa summits. Slopes range from 5 to 120 percent. Mean annual precipitation is about 1,041 mm and the mean annual air temperature is about -1.7 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, isotic Lithic Humicryepts
TYPICAL PEDON: Telluride very cobbly loam, on a southeast facing 8 percent basin slope on alpine rangeland at an elevation of 3,609 meters. (colors are for dry soil unless otherwise noted. When described on September 18, 1987, the soil was moist throughout.)
A--0 to 25 cm; very dark gray (10YR 3/1) very cobbly loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure parting to weak very fine granular; soft, very friable, nonsticky and nonplastic; 15 percent gravel, 25 percent cobbles; moderately acid (pH 6.0); clear smooth boundary. (18 to 38 cm thick)
Bw1--25 to 36 inches; brown (7.5YR 4/4) very gravelly loam, dark brown (7.5YR 3/2) moist; weak medium granular structure; soft, very friable, nonsticky and nonplastic; 55 percent gravel; moderately acid (pH 6.0); clear wavy boundary.
Bw2--36 to 46 cm; brown (7.5YR 5/4) extremely channery sandy loam, dark brown (7.5YR 3/4) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; 85 percent channery fragments; moderately acid (pH 5.8); abrupt wavy boundary. (combined thickness of Bw horizons - 10 to 46 cm)
R--46 cm; highly fractured hard andesite bedrock.
TYPE LOCATION: Hinsdale County, Colorado; about 11 km east of Ouray, Colorado; within an unsectionized area of Uncompahgre National Forest, estimated to be in Section 32, T. 44 N., R. 6 W.; USGS Wetterhorn Peak USGS Quad; Lat. 38 degrees, 00 minutes, 59 seconds N. and Long. 107 degrees, 32 minutes, 15 seconds W.; NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture regime: typic udic; dry in some part of the moisture control section for less than 45 cumulative days
Mean annual soil temperature: 0.6 to 2.8 degrees C.
Depth to lithic contact: 25 to 50 cm
Thickness of umbric epipedon: 18 to 38 cm
Lithology of rock fragments: andesite, rhyolite, breccia, basalt, or tuff
Particle-size control section:
Clay content: 15 to 27 percent
Rock fragment content: 35 to 85 percent
Some pedons may have an organic surface layer
A horizon
Hue: 7.5YR or 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 1 or 2, dry or moist
Texture: loam, silt loam
Rock fragments: 35 to 55 percent total rock fragments; 0 to 20 percent gravel, 20 to 40 percent cobbles, 0 to 10 percent stones.
Base saturation: 30 to 45 percent.
Reaction (pH): 4.5 to 6.0
Bw horizon
Hue: 7.5YR or 10YR
Value: 4 to 6 dry, 3 or 4 moist
Chroma: 2 to 4, dry or moist
Texture: loam, sandy loam
Rock fragments: 50 to 85 percent total rock fragments; 0 to 60 percent gravel, 0 to 40 percent cobbles, 0 to 85 percent channers, 0 to 55 percent flagstones or stones.
Base saturation: 30 to 45 percent.
Reaction (pH): pH 4.5 to 6.0
COMPETING SERIES:
Burgerbutte (OR) - have a xeric soil moisture regime
Crawfish (OR) - are very shallow to lithic bedrock
Eastlakebasin (OR) - have a xeric soil moisture regime
Snowtell (CA) - are very shallow to lithic bedrock and have a xeric soil moisture regime
GEOGRAPHIC SETTING:
Parent material - slope alluvium or colluvium over residuum and till from andesite, rhyolite, breccia, basalt, or tuff
Landform - basin floors, ridges, mountain slopes, and mesa summits
Slopes - 5 to 120 percent
Elevation - 3,350 to 4,270 meters
Mean annual air temperature - -3.3 to 1.1 degrees C.
Mean annual precipitation - 711 to 1,245 mm
Frost-free period - 20 to 45 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: well drained; medium to very high runoff; moderate permeability.
USE AND VEGETATION: This soil is used for summer grazing and wildlife habitat. Potential native vegetation is kobresia, tufted hairgrass, alpine fescue, alpine bluegrass, and Ross' avens. It is in the Shallow Alpine Range Site, RS 308.
DISTRIBUTION AND EXTENT: Western Colorado in LRR E and MLRA 48A. The series is of moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Ouray Soil Survey Area, Uncompahgre National Forest, Hinsdale County, Colorado, 1997. The name comes from the city of Telluride.
REMARKS:
Diagnostic horizons and features recognized in this pedon:
Umbric epipedon: 0 to 36 cm (A and Bw1 horizons)
Lithic contact: 46 cm to hard andesite bedrock (R layer)
Particle-size control section: 25 to 46 cm (Bw1 and Bw2 horizons)
Telluride soils have a cryic temperature regime and are in an udic soil moisture regime with a typic subclass.
Further study is needed to determine if these soils contain andic materials.
The 06/2002 revision changes the mineralogy class from mixed to isotic.
National Cooperative Soil Survey
U.S.A.