LOCATION LUCKY CO+MT WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Ustic Argicryolls
TYPICAL PEDON: Lucky gravelly sandy loam - grassland. (Colors are for dry soil unless otherwise noted.)
A--0 to 8 inches; very dark grayish brown (10YR 3/2) gravelly sandy loam, very dark brown (10YR 2/2) moist; moderate fine and very fine granular structure; soft, very friable; 15 percent pebbles; neutral (pH 6.6); clear smooth boundary. (4 to 9 inches thick)
BA--8 to 12 inches; brown (10YR 5/3) gravelly heavy sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to moderate fine granules; slightly hard, very friable; few thin waxy patches presumed to be silicate clay or other clay-sized materials on faces of peds; 15 percent pebbles; neutral (pH 6.8); clear smooth boundary. (2 to 6 inches thick)
Bt--12 to 22 inches; brown (7.5YR 5/4) gravelly sandy clay loam, dark brown (7.5YR 4/4) moist; moderate medium subangular blocky structure; hard, friable; thin nearly continuous waxy coatings presumed to be silicate clay or other clay-sized materials on the surfaces of the peds; 25 percent pebbles; neutral (pH 7.0); gradual smooth boundary. (6 to 15 inches thick)
BC--22 to 28 inches; yellowish brown (10YR 5/4) gravelly light sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; hard, friable; few thin waxy patches presumed to be silicate clay or other clay-sized materials on the surfaces of the peds; 25 percent pebbles; neutral (pH 7.0); gradual wavy boundary. (3 to 8 inches thick)
R--28 inches; gneiss bedrock.
TYPE LOCATION: Gunnison County, Colorado; NE1/4 Sec. 10, T. 48 N., R. 1 E.
RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 40 to 44 degrees F. The mollic epipedon is 7 to 15 inches thick. Depth to the base of the argillic horizon is 15 to 40 inches. Depth to bedrock ranges from 20 to 40 inches. The soils are 60 to 100 percent base saturated. Rock fragments range from 0 to 35 percent and are mainly pebbles and cobbles. In some pedons subhorizons redder than 7.5YR are present but the major part of the solum or any C horizon above the bedrock has hue of 7.5YR or yellower. These soils are dry in some part of the moisture control section for some time in most years.
The A horizon has hue of 2.5Y through 7.5YR, value of 3 through 5 dry, 2 or 3 moist, with chroma of 1 through 3. It is medium acid to mildly alkaline.
The Bt horizon has hue of 2.5Y through 7.5YR, value of 4 through 7 dry, 3 through 6 moist, with chroma of 1 through 6. It is usually sandy clay loam and has 18 to 35 percent clay, 5 to 35 percent silt, and 40 to 70 percent sand with more than 35 percent being fine sand or coarser. This horizon is medium acid to mildly alkaline and remains constant or becomes slightly more alkaline with increasing depth. In some pedons a C and thin Cr horizons occur above 40 inches.
COMPETING SERIES: These are the Amsden, Buffork, Cific, Croydon, Dra, (T) Gebson, Gelkie, Hourglass, Inchau, Kezar, Kittredge, Leavitt, Lymanson, Lyonman, Michelson, Miracle, Monad, (T) Monida, Morset, Mult, Newlands, Oro Fino, Passcreek, Philipsburg, Primeaux, Rammel, (T)Slacks, Sponseller, Swede, Tingey, Tripit, Troutdale, Wellsville, Woosley, and Youga series. Amsden, Croydon, Gebson, Gelkie, Hourglass, Kittredge, Leavitt, Lyonman, Michelson, Monad, Monida, Morset, Oro Fino, Philipsburg, Swede, Tingey, Wellsville, and Youga soils lack a lithic contact at depths less than 40 inches. Buffork, Cific, Inchau, Lymanson, Tripit, and Troutdale soils have a paralithic contact at depths of less than 40 inches. Cific, Dra, Passcreek, Rammel, and Woosley soils are calcareous in the lower part of the solum and in the C horizon and have continuous subhorizons of secondary calcium carbonate accumulation. Miracle soils have hue of 5YR or redder in a major part of the control section. Mult, Newlands, and Primeaux soils have less than 35 percent fine or coarser sand in the argillic horizon. Kezar soils have a large proportion of coarse and very coarse angular sand and have extremely hard consistence when air-dry. (T)Slacks soils are usually moist in the soil moisture control section when the temperature is greater than 41 degrees F.
GEOGRAPHIC SETTING: Lucky soils are on mountain side slopes and ridges. Slopes range from 2 to 50 percent. The soil formed in moderately fine to moderately coarse parent materials weathered from gneiss, shist, or hard tuff. Elevation ranges from 7,500 to 9,000 feet. In more northern latitudes, elevation ranges down to 6,000 feet. The average annual precipitation is 20 inches, ranging from 18 to 25 inches, with peak periods of precipitation in the spring and summer. Mean annual temperature ranges from 38 to 42 degrees F, and mean summer temperature is 55 degrees F. The frost-free season is less than 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cabin and Sapphire soils. Cabin soils have loamy-skeletal 2C horizons at depths of less than 40 inches. Sapphire soils have ochric epipedons, albic horizons, and A&B horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium or slow runoff; moderate or rapid permeability.
USE AND VEGETATION: These soils are used principally for native pastureland and for recreational purposes. Native vegetation consists of big sage, Oregon grape, bitterbrush, and various grasses.
DISTRIBUTION AND EXTENT: High mountainous areas of central Colorado and adjacent parts of Wyoming. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Gunnison County, Colorado; 1973.