LOCATION ORCAP UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, carbonatic Typic Cryorthents
TYPICAL PEDON: Orcap very gravelly clay loam; forest, on a 36 percent southeast facing slope. (Colors are for air dry soil unless otherwise stated.)
A--0 to 4 inches; yellowish red (5YR 5/6) very gravelly clay loam, dark reddish brown (5YR 3/3) moist; weak fine and very fine granular structure; slightly hard, friable, sticky and plastic; many fine and very fine roots; many fine and very fine interstitial pores; 40 percent gravel; violently effervescent, carbonates are disseminated; neutral (pH 7.4); clear smooth boundary.
Bw1--4 to 7 inches; red (2.5YR 5/6) gravelly clay loam, dark reddish brown (2.5YR 3/4) moist; weak medium subangular blocky structure parting to weak fine and very fine subangular blocky; hard, firm, sticky and plastic; few medium, common fine and very fine roots; common fine and very fine pores; 25 percent gravel; violently effervescent, carbonates are disseminated; mildly alkaline (pH 7.4); clear wavy boundary.
Bw2--7 to 12 inches; red (2.5YR 4/6) gravelly clay loam, red (2.5YR 4/6) moist; weak medium and fine subangular blocky structure, parting to weak very fine subangular blocky; hard, firm, sticky and plastic; few fine and very fine roots; few fine and very fine pores; 20 percent gravel; violently effervescent; carbonates are disseminated; mildly alkaline (pH 7.6); gradual wavy boundary.
Bw3--12 to 22 inches; red (2.5YR 5/6) gravelly clay loam, red (2.5YR 4/6) moist; weak coarse and medium subangular blocky structure, parting to weak medium and fine subangular blocky; very hard, firm, sticky and plastic; few very fine roots; few fine and very fine pores; 30 percent gravel; violently effervescent, carbonates are disseminated; mildly alkaline (pH 7.6); gradual wavy boundary.
R--22 inches; fractured sedimentary bedrock.
TYPE LOCATION: Iron County, Utah; about 0.5 mile southeast of the junction of the Dry Lakes Road and the Brainhead Road, 1,000 feet east and 500 feet north of the southwest corner of section 34, Township 35 South, Range 9 West. 37 degrees 42 minutes 22 seconds north latitude, 112 degrees 51 minutes 42 seconds west longitude.
RANGE IN CHARACTERISTICS: The soil moisture regime is udic. The mean annual soil temperature ranges from 35 to 41 degrees F., and mean summer soil temperature at a depth of 20 inches is 50 to 59 degrees F.
Depth to fractured bedrock ranges from 20 to 40 inches. Calcium carbonate equivalent averages 40 to 60 percent, including the carbonates in the coarse fragments of less than 20 millimeters size, between 10 inches and the paralithic contact.
The A horizon has hue of 2.5YR or 5YR, value of 4 or 5 dry, and chroma of 3 to 6. It is gravelly loam or very gravelly clay loam, with 20 to 60 percent rock fragments that are predominantly gravel and cobbles. It is neutral to moderately alkaline.
The Bw horizon has hue of 2.5YR or 5YR, value of 4 to 6 dry and 2 to 4 moist, and chroma of 2 through 6. It is gravelly loam, loam or gravelly clay loam with 5 to 35 percent rock fragments that are predominantly gravel and cobbles. It is mildly alkaline or moderately alkaline.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Orcap soils are on mountainsides under coniferous forest at elevations of 7,600 to 9,700 feet. Slopes are 15 to 70 percent. These soils formed in residuum and colluvium from sandstone and limestone. The mean annual precipitation is 22 to 30 inches. The mean annual air temperature is 34 to 40 degrees and mean summer temperature is 46 to 52 degrees F. The freeze-free season is 40 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Amherst, Baird Hollow, Bushvalley, Faim, Mord, Pagoda and Seth series. All these have mollic epipedons and argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used mainly for grazed woodland, wildlife habitat, recreation and watershed. Vegetation is dominantly Douglas-fir, White fir, Ponderosa pine, mountain brome, Oregon grape and mountain snowberry.
DISTRIBUTION AND EXTENT: Southern Utah. This soil is not extensive. MLRA 47
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Iron-Washington Survey Area, Iron County, Utah, 1997.
REMARKS: The diagnostic Horizons and features that are recognized in this pedon are:
Ochric epipedon - The zone from the surface of the soil to 4 inches. (A horizon)
In October 1994 the classification was changed from a Cryochrept to a Cryorthent because there is no evidence of a calcic or cambic horizon in the type location pedon. The classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998".