LOCATION RUBY COEstablished Series
TAXONOMIC CLASS: Fine-loamy over fragmental, mixed, superactive Ustic Argicryolls
TYPICAL PEDON: Ruby gravelly sandy loam, grassland. (Colors are for dry soil unless otherwise noted.)
A1--O to 6 inches; brown (7.5YR 5/2) gravelly sandy loam, dark brown (7.5YR 3/2) moist; moderate fine granular structure; soft, very friable; 15 percent gravel; slightly acid; clear smooth boundary. (5 to 8 inches thick)
B2t--6 to 13 inches; brown (7.5YR 5/4) stony clay loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, slightly sticky and slightly plastic; peds are hard, very friable; thin nearly continuous clay films on peds and in root channels and pores; 25 percent stones; slightly acid; gradual wavy boundary. (5 to 12 inches thick)
IIC--13 to 60 inches; fragmental beds of highly fractured rhyolite consisting of overlapping flagstones with interstices 1/2 to 1-inch wide between the rocks and not completely filled with fine textured material.
TYPE LOCATION: Saguache County, Colorado; 1/2 mile north of the Rock Creek Cow Camp in the NW1/4 Sec. 21, T.46 N., R. 1 W.
RANGE IN CHARACTERISTICS: Base saturation ranges from 60 to 100 percent but is usually greater than 80 percent. Typically the B2t horizon extends to the fragmental substratum but thin C horizons occur in some pedons. Depth to the fragmental IIC horizon ranges from 10 to 20 inches. Depth to the base of the argillic horizon ranges from 10 to 20 inches. Rock fragments range from 5 to 35 percent by volume in a major part of the solum above the IIC horizon and are mainly flagstones ranging in diameter from 10 to 24 inches. The solum ranges from slightly acid to mildly alkaline. The mean annual soil temperature is 38 degrees F., and the mean summer soil temperature is 54 degrees F.
The A horizon has hue of 2.5Y through 7 5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 1 through 3.
The B2t horizon has hue of 2.5Y through 7.5YR, value of 5 through 7 dry, 3 through 6 moist, and chroma of 1 through 6. It is typically stony loam or stony clay loam, and the fine earth fraction has 18 to 35 percent clay, 20 to 55 percent silt and 20 to 50 percent sand, with less than 35 percent being fine or coarser sand.
COMPETING SERIES: These are the Catar and Sizer series. Catar soils have more than 35 percent coarse fragments in the solum and have coarse fragments that are mainly less than ten inches in diameter. Sizer soils have hue of 5YR or redder, overlie beds of cinders, and have a significant amount of pyroclastic material in the control section.
GEOGRAPHIC SETTING: The Ruby soils are on gently sloping to moderately steep mesa tops and ridges. The soils formed in stony materials weathered residually from highly fractured rhyolite or rhyolitic bedrock. At the type location the average annual precipitation is 20 inches with peak periods of precipitation during the spring and summer. The mean annual temperature is 34 degrees F., and the mean summer temperature is 56 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Passar and Sapinero soils. Passar soils have fine textured argillic horizons with more than 35 percent coarse fragments, and lack fragmental substratums. Sapinero soils lack mollic epipedons, have albic horizons, and have fragmental substratums at depths of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used principally as native pastureland or for recreational purposes. Native vegetation is mainly big sagebrush, native bluegrass, Letterman needlegrass, and Thurber fescue.
DISTRIBUTION AND EXTENT: Mountainous areas of central Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Saguache County, Colorado, 1974.
REMARKS: Last updated by the state 2/75.