LOCATION ORCKY UTEstablished Series
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Xeric Haplocalcids
TYPICAL PEDON: Orcky gravelly fine sandy loam, rangeland. (Colors are for air-dry soil unless otherwise noted.)
A--0 to 3 inches; light yellowish brown (10YR 6/4) gravelly fine sandy loam, brown (10YR 4/3) moist; weak fine granular structure; soft, friable, slightly sticky and slightly plastic; few very fine roots; few very fine pores; 30 percent pebbles; moderately calcareous; carbonates are disseminated; moderately alkaline (pH 8.2); abrupt smooth boundary. (3 to 11 inches thick)
Bw--3 to 11 inches; very pale brown (10YR 7/4) gravelly fine sandy loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; soft, friable, slightly sticky and slightly plastic; few very fine roots; few very fine pores; 30 percent pebbles; moderately calcareous; carbonates are disseminated; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 13 inches thick)
Bk--11 to 17 inches; very pale brown (10YR 7/4) gravelly fine sandy loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; 30 percent pebbles; strongly calcareous; carbonates are disseminated and coats rock fragments; moderately alkaline (pH 8.4); clear smooth boundary. (6 to 18 inches thick)
2Bk1--17 to 29 inches; very pale brown (10YR 7/4) extremely gravelly loamy sand, brown (10YR 5/3) moist; single grained; loose; few very fine roots; 65 percent pebbles; moderately calcareous; carbonates are disseminated and as coats on rock fragments; moderately alkaline (pH 8.4); gradual wavy boundary. (7 to 18 inches thick)
2Bk2--29 to 60 inches; very pale brown (10YR 7/3) extremely gravelly sand, brown (10YR 5/3) moist; single grained; loose; few very fine roots; 65 percent pebbles; moderately calcareous; carbonates are disseminated and as coats on rock fragments; moderately alkaline (pH 8.0).
TYPE LOCATION: Juab County, Utah; 1 mile south and 2 1/2 miles west of Mills; 100 feet east and 2,470 feet south of the northwest corner of sec. 34, T. 15 S., R. 2 W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 45 to 52 degrees F. The mean summer temperature is 66 to 70 degrees F. These soils are usually dry but are moist in some part of the moisture control section for 40 to 50 percent of the time that the soil temperature is above 41 degrees F. They are continually dry for 70 to 80 days during the summer months.
Depth of the A and Bw horizons range from 11 to 20 inches. The calcium carbonate equivalent ranges from 15 to 25 percent in the calcic horizon.
The upper part of the particle-size control section averages between 10 and 18 percent clay and has less than 50 percent sand that is fine sand or coarser. The lower part of the particle-size control section ranges from sand to extremely gravelly loamy sand and has as much as 70 percent pebbles.
The A horizon has values of 5 or 6 dry, 4 or 5 moist and chroma of 2 through 4. Rock fragments range from 15 to 35 percent.
The Bw horizon has value of 6 or 7 dry, 4 or 5 moist and chroma of 3 or 4. Textures range from gravelly loam to gravelly fine sandy loam. Rock fragments range from 15 to 35 percent.
The Bk horizon has values of 6 or 7 dry and 5 or 6 moist; chromas are 2 through 4. Textures range from gravelly loam to gravelly fine sandy loam. Rock fragments range from 15 to 35 percent. It is moderately alkaline or strongly alkaline.
The texture of the 2Bk horizon ranges from loamy sand to extremely gravelly sand. It has more than 35 percent rock fragments.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Orcky soils are mainly on alluvial fans, lake terraces and lake terrace escarpments at elevations of 4,500 to 5,200 feet. Slopes are 4 to 40 percent. The soils formed in lake sediments and alluvium derived from igneous and sedimentary rocks. The climate is semiarid, the mean annual temperature is 45 to 52 degrees F. The mean annual precipitation is 8 to 12 inches. The freeze-free period is 110 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Genola, Jericho, Heist, Hiko Peak, Linoyer, Medburn, and Shabliss soils. Genola, Heist, Linoyer, and Medburn soils all lack calcic horizons. Jericho and Shabliss soils have a duripan at depths of less than 20 inches.
DRAINAGE AND PEREMABILITY: Somewhat excessively drained; medium runoff; rapid permeability.
USE AND VEGETATION: Used primarily for range and wildlife habitat. A few small areas are cultivated. Potential plants are mainly big sagebrush, little rabbitbrush, Indian ricegrass, and needleandthread.
DISTRIBUTION AND EXTENT: Central Utah. This series is moderately extensive. 10,000 acres mapped in Juab and Utah Counties.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Fairfield-Nephi Soil Survey Area, Utah, 1980. The name is coined.
REMARKS: Diagnostic horizons and features in this pedon include:
Calcic horizon - from 11 to 60 inches (Bk, 2Bk1, and 2Bk2 horizons).
The classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998".