LOCATION DERA UT+AZEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, mesic Typic Haplocalcids
TYPICAL PEDON: Dera gravelly sandy loam-rangeland (colors are for air-dry soil unless otherwise noted.)
A--0 to 4 inches; light brownish gray (10YR 6/2) gravelly sandy loam, brown (10YR 4/3) moist; moderate medium platy structure; slightly hard, firm; few fine and medium roots; many fine vesicular pores; 20 percent gravel; strongly effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (2 to 4 inches thick)
Bw--4 to 13 inches; pale brown (10YR 6/3) gravelly sandy loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, friable; few fine and medium roots; few fine vesicular pores; 20 percent gravel; strongly effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (5 to 14 inches thick)
Bk--13 to 22 inches; very pale brown (10YR 7/3) gravelly sandy loam, pale brown (10YR 6/3) moist; massive; soft, friable, few fine roots; 35 percent gravel; violently effervescent; strongly alkaline (pH 9.0); gradual wavy boundary. (9 to 28 inches thick)
C1--22 to 45 inches; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, 40 percent gravel; violently effervescent; moderately alkaline (pH 8.4); diffuse wavy boundary. (6 to 23 inches thick)
C2--45 to 60 inches; light yellowish brown (10YR 6/4) very gravelly sandy loam; yellowish brown (10YR 5/4) moist; massive; soft, very friable, 50 percent gravel; violently effervescent, moderately alkaline (pH 8.4)
TYPE LOCATION: Millard County, Utah; 100 feet east and 1,300 feet south of the northwest corner of sec. 25, T. 24 S., R. 17 W.; Pine Valley Hardpan USGS Quad; latitude 38 degrees, 42 minutes, 02 seconds N. and longitude 113 degrees, 42 minutes, 41 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: Dry in all parts of 75 to 85 percent of the time the soil temperature is above 41 degrees F.
Mean annual soil temperature: 50 to 53 degrees F.
Depth to calcic horizon: 7 to 18 inches.
Particle-size control section (weighted average):
Clay content: 8 to 18 percent.
Rock fragments: 35 to 65 percent; mostly gravel and cobbles.
Calcium carbonate equivalent: Usually less than 30 percent in the fine earth fraction; 40 to 65 percent in the less than 20 mm. in diameter fraction.
A horizon:
Hue: 10YR or 7.5YR.
Value: 5 to 7 dry, 4 to 6 moist.
Chroma: 2 to 4.
Reaction: Slightly alkaline to strongly alkaline.
Bw horizon:
Hue: 10YR or 7.5YR.
Value: 5 to 7 dry, 4 to 6 moist.
Chroma: 3 or 4.
Texture: Commonly sandy loam, but ranges to loam, or sandy clay loam.
Clay content: 15 to 26 percent.
Rock fragments: 10 to 55 percent, mainly gravel.
Reaction: Slightly alkaline to very strongly alkaline.
Bk and C horizons:
Hue: 10YR or 7.5YR.
Value: 5 to 8 dry, 4 to 8 moist.
Chroma: 2 to 6.
Texture: Loam or sandy loam; subhorizons of loamy sand are in the lower part of some pedons.
Clay content: 5 to 18 percent.
Rock fragments: 35 to 65 percent, mainly gravel.
Reaction: Slightly alkaline to very strongly alkaline.
Other features: Some pedons contain gypsum in the lower part of the profile.
COMPETING SERIES: This is the Mariano series. Mariano soils have a lithologic discontinuity between eolian and alluvial parent material and have mean annual soil temperature ranging from 54 to 58 degrees F.
GEOGRAPHIC SETTING: Dera soils occur on long alluvial fans, fan terraces, fan skirts, colluvial slopes and lake terraces with gradients of 0 to 15 percent. They formed in alluvium, colluvium and lake sediments primarily from igneous and sedimentary rock, including limestone, dolomite and small amounts of quartzite. These soils occur at elevations of 4,000 to 6,500 feet. The average annual precipitation is 5 to 10 inches. The mean annual air temperature ranges from 45 to 55 degrees F, with mean summer temperatures ranging from 69 to 72 degrees F. The frost-free season is 100 to 125 days in Utah and to 180 days in Arizona.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bluewing, Certa, Cliffdown, Koeta and Sardo soils. Bluewing and Cliffdown soils lack calcic horizons. Koeta soils are less than 20 inches deep over bedrock. Certa soils have less than 40 percent carbonates in the control section.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Used for rangeland and wildlife habitat. The native vegetation is shadscale, galleta, blue grama, sand dropseed and some Mormon tea.
DISTRIBUTION AND EXTENT: Southwest Utah and Northern Arizona. The series is of moderate extent. MLRA 28A and 28B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Mohave County, Arizona (Shivwits Area), 1994.
REMARKS: Diagnostic horizons and features in this pedon include:
Ochric epipedon: the zone from 0 to 4 inches. (A horizon)
Calcic horizon: the zone from 13 to 22 inches. (Bk horizon)
In Utah this series is correlated with Desert range sites.
Classification changed from Typic Calciorthids to Typic Haplocalcids in 8/94, due to an amendment to Soil Taxonomy.
Lab data is available for the similar soils in these pedon numbers: 66UT027005, 66UT027008, 68UT027005. Further investigation is needed on the sodium content of this series.