LOCATION CARBOL             CO+WY
Established Series
Rev. RHM/GB
02/1999

CARBOL SERIES


The Carbol series consists of shallow, well drained soils that formed in material weathered from granite and sandstone. These soils are on upland hills, plateaus, and mountainsides. Slopes range from 3 to 60 percent. The mean annual precipitation is about 18 inches and the mean annual temperature is about 34 degrees F.

TAXONOMIC CLASS: Loamy, mixed, superactive Lithic Argicryolls

TYPICAL PEDON: Carbol gravelly coarse sandy loam - grassland. (Colors are for dry soil unless otherwise noted.)

A--0 to 7 inches; very dark grayish brown (10YR 3/2) gravelly coarse sandy loam, very dark brown (10YR 2/2) moist; moderate medium granular structure; soft, very friable; 20 percent fine and very fine granular granitic pebbles; neutral; gradual smooth boundary. (4 to 10 inches thick)

Bt--7 to 14 inches, brown (7.5YR 4/3) gravelly sandy clay loam, dark brown (7.5YR 3/3) moist; moderate coarse subangular blocky structure parting to medium subangular blocky; hard, friable, slightly sticky and slightly plastic; peds are extremely hard, very friable; thin continuous clay films on peds and in root channels and pores; 30 percent fine and very fine angular granitic pebbles; neutral; gradual smooth boundary. (4 to 12 inches thick)

R--14 inches; hard granite.

TYPE LOCATION: Gunnison County, Colorado; Sec. 26, T. 46 N., R. 15 W.

RANGE IN CHARACTERISTICS: Base saturation ranges from 60 to 100 percent. Thin C horizons occur in some pedons. Depth to the lithic contact ranges from 10 to 20 inches. Rock fragments range from 0 to 35 percent by volume in a major part of the solum and C horizon above the R horizon. They are typically less than 1 inch in diameter and range from 1/8 to 10 inches in diameter. The solum ranges from moderately acid to mildly alkaline. Mean annual soil temperature is 38 to 42 degrees F, and mean summer soil temperature is 46 to 57 degrees F without an O horizon.

The A horizon has hue of 2.5Y through 7.5YR, value of 3 through 5 dry, 2 or 3 moist, and chroma of 1 through 3.

The Bt horizon has hue of 2.5Y through 7.5YR, value of 4 through 7 dry, 3 through 6 moist, and chroma of 1 through 6. It is typically gravelly sandy clay loam and less commonly is loam or clay loam. It has 18 to 35 percent clay, 5 to 30 percent silt, and 40 to 75 percent sand with more than 35 percent being fine or coarser sand. Within the sand fraction a large proportion is medium, coarse, and very coarse angular sand which has a large proportion of flat bearing surfaces between sand grains. Some pedons have a thin C horizon above the bedrock with more than 35 percent rock fragments.

COMPETING SERIES: These are the Chittum (WY), Gilispie (MT), and Katseanes (ID) series. Gilispie and Chittum soils have Bt horizons with less than 35 percent fine or coarser sand and with only small amounts of coarse and very coarse angular sand. Katseanes soils have moderately acid control sections and have higher amounts of silt in the control section.

GEOGRAPHIC SETTING: Carbol soils are on upland hills, plateaus, and mountainsides. Slopes range from 3 to 60 percent. The soils formed in parent material weathered residually from granite and sandstone. Mean annual precipitation is 16 to 25 inches. Mean annual temperature is 33 to 40 degrees F and mean summer temperature is 44 to 55 degrees F. Elevation ranges from 7,500 to 10,000 feet from north to south in Colorado. Frost-free period ranges from 50 to 75 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Schofield and Uinta soils. Schofield and Uinta soils lack mollic epipedons, have continuous E horizons, and lack bedrock above a depth of 40 inches.

DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderately rapid to moderate permeability above bedrock.

USE AND VEGETATION: These soils are used mainly as native pastureland and for recreational purposes. Native vegetation is mainly big sagebrush, Arizona fescue, pine dropseed, Indian ricegrass, and widely spaced ponderosa pine and fir.

DISTRIBUTION AND EXTENT: High mountain areas of central and northwestern Colorado and northern and central Wyoming. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Gunnison County, Colorado, 1974.

REMARKS: Diagnostic features include an argillic horizon at 7 to 14 inches, a mollic epipedon 7 to 10 inches thick, and a lithic contact at 14 inches. Last updated by the state 2/91.


National Cooperative Soil Survey
U.S.A.