LOCATION SPACE CITY COEstablished Series
TAXONOMIC CLASS: Mixed, frigid Typic Torripsamments
TYPICAL PEDON: Space City loamy fine sand - grassland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 9 inches; grayish brown (10YR 5/2) loamy fine sand, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; soft, very friable; noncalcareous; mildly alkaline; gradual smooth boundary. (6 to 10 inches thick)
C1--9 to 30 inches; brown (10YR 5/3) loamy fine sand, dark grayish brown (10YR 4/2) moist; single grained; loose; noncalcareous; mildly alkaline; gradual wavy boundary. (10 to 34 inches thick)
C2ca--30 to 60 inches; brown (10YR 5/3) loamy fine sand, dark grayish brown (10YR 4/2) moist; single grained; loose; visible secondary carbonate occurring as concretions, in thin seams and streaks, and as coatings on sand fragments; moderately alkaline.
TYPE LOCATION: Alamosa County, Colorado; 20 feet east of the northwest corner of Sec. 30, T. 38 N., R. 13 E.
RANGE IN CHARACTERISTICS: The Space City soils are usually noncalcareous to depths of 18 to 30 inches but depth to uniformly calcareous material ranges from 10 to 40 inches. Exchangeable sodium ranges from 0 to 14 percent in a majority of subhorizons in the control section. Depth to continuous subhorizons of visible secondary calcium carbonate and/or sulfate ranges from 15 to 40 inches. The particle-size control section is loamy fine sand, loamy sand or sand. Rock fragments range from 0 to 15 percent and are mainly less than 3 inches in diameter. The mean annual soil temperature ranges from 43 to 46 degrees F., and the mean summer soil temperature ranges from 60 to 64 degrees F.
The A horizon has hue of 2.5Y through 7.5YR, value of 5 through 7, 3 through 6 moist, and chroma of 1 through 4. It is neutral or mildly alkaline.
The C horizon has hue of 2.5Y through 7.5YR, value of 5 or 6, 3 or 4 moist, and chroma of 2 through 4. It ranges from mildly to strongly alkaline, and has 2 to about 14 percent calcium carbonate equivalent of the fine earth fraction.
COMPETING SERIES: These are the (T) Bodorumpe, Corlett, Costilla, and Cotopaxi series. Bodorumpe soils have a paralithic contact at depths of less than 40 inches. Corlett soils are calcareous at or near the surface and have more than 15 percent exchangeable sodium. Costilla soils have more than 15 percent rock fragments. Cotopaxi soils are noncalcareous to depths of more than 40 inches.
GEOGRAPHIC SETTING: Space City soils are in sloping dune-like areas along the margins of intermountain valleys and basins or small ridges on the valley floors. Slope gradients range from O to 15 percent. The soils formed in wind reworked sediments of mixed mineralogy. The average annual precipitation is 7 inches, with peak periods of precipitation in the spring and early summer. Mean annual temperature is 40 to 44 degrees F., and mean summer temperature is 59 to 62 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Corlett and Costilla soils.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; slow runoff; rapid permeability.
USE AND VEGETATION: These soils are used principally as native pastureland; however, they are used for irrigated grass where spray irrigation is developed. Native vegetation is mainly blue grama, spiney muhly, short and tall rabbitbrush, and greasewood.
DISTRIBUTION AND EXTENT: The San Luis Valley Area of south-central Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Alamosa County, Colorado, 1974.
REMARKS: OSED scanned by NSSQA and cleaned up by Colorado. Last revised by state on 5/81.