LOCATION DECCA UTEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Xeric Calciargids
TYPICAL PEDON: Decca sandy loam--irrigated cropland. (Colors are air-dry soil unless otherwise stated.) About 25 percent of the surface is covered with gravel.
A--0 to 5 inches; pale brown (10YR 6/3) sandy loam, dark brown (10YR 3/3) moist; moderate coarse subangular blocky structure parting to moderate medium subangular blocky; soft, very friable, nonsticky and nonplastic; few medium roots, common fine roots, and many very fine roots; few coarse pores and many medium, fine, and very fine pores; 5 percent gravel; moderately alkaline pH 8.4); abrupt smooth boundary.
Bt1--5 to 13 inches; brown (7.5YR 5/4) sandy clay loam, dark brown (7.5YR 3/4) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; few medium roots, common fine roots, and many very fine roots; few medium pores and common fine and very fine pores; common distinct clay films on faces of peds; 10 percent gravel; moderately alkaline (pH 8.0); clear smooth boundary.
Bt2--13 to 21 inches; brown (7.5YR 5/4) sandy clay loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, friable, moderately sticky and moderately plastic; few medium and fine roots and common very fine roots; many fine and very fine pores; common faint clay films on faces of peds and bridging sand grains; 10 percent gravel; moderately alkaline (pH 8.0); abrupt smooth boundary.
Bk--21 to 30 inches; light brown (7.5YR 6/4) sandy clay loam, brown (7.5YR 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine roots and common very fine roots; few very fine pores; 5 percent gravel; strongly effervescent, carbonates are in common fine filaments; moderately alkaline (pH 8.4); clear wavy boundary.
2C1--30 to 37 inches; light brown (7.5YR 6/4) very gravelly loamy sand, brown (7.5YR 4/4) moist; single grain; loose, nonsticky and nonplastic; few fine roots and many very fine roots; common fine interstitial pores and many very fine interstitial pores; 50 percent gravel; strongly effervescent, carbonates are in common fine filaments and partially coat gravel; moderately alkaline (pH 8.4); clear wavy boundary.
2C2--37 to 60 inches; pale brown (10YR 6/3) very gravelly sand, dark brown (10YR 3/3) moist; single grain; loose, nonsticky and nonplastic; few fine roots and many very fine roots; many fine and very fine interstitial pores; 50 percent gravel; strongly effervescent, carbonates partially coat gravel; moderately alkaline (pH 8.4).
TYPE LOCATION: Iron County, Utah; About 7.9 miles northwest of Beryl Junction, about 200 feet north and 2,500 feet west of the southeast corner of sec. 18, T. 35 S., R. 17 W.
RANGE IN CHARACTERISTICS:
Soil moisture: These soils are dry in the moisture central section for 50 to 75 percent of the time the soil temperature is above 41 degrees F. The moisture regime is aridic bordering on xeric.
Mean annual soil temperature at a depth of 20 inches: 47 to 52 degrees F.
Mean summer soil temperature at a depth of 20 inches: 65 to 68 degrees F.
Depth to secondary calcium carbonate: 10 to 21 inches.
A horizon:
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3.
Bt and Btk horizon (when present):
Hue: 7.5YR or 10YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 to 4
Texture: Sandy clay loam, loam, clay loam.
Clay content: 18 to 35 percent.
Rock fragments: 0 to 15 percent gravel.
Reaction: neutral to moderately alkaline.
Bk horizon:
Hue: 7.5YR or 10YR.
Value: 6 to 8 dry, 4 to 6 moist.
Chroma: 3 or 4.
Texture: Sandy clay loam, loam, clay loam.
Clay content: 18 to 35 percent.
Rock fragments: 5 to 35 percent.
Reaction: Slightly alkaline or moderately alkaline.
2C horizon:
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry and 3 or 4 moist.
Chroma: 2 to 4.
Texture: Very gravelly loamy sand to extremely gravelly sand.
Rock fragments: 35 to 90 percent, mainly gravel.
Reaction: Slightly alkaline to strongly alkaline.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Decca soils occur on fan remnants, stream terraces and rolling hills. Slopes range from 0 to 30 percent. These soils formed in stratified alluvium derived from mixed igneous and quartzite parent rock. Elevations range from 5,000 to 5,900 feet. Mean annual temperature is 45 to 50 degrees F. Mean summer temperature is 66 to 69 degrees F. The average annual precipitation is 9 to 12 inches and the freeze-free period is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hiko Peak and Fruitland soils. Hiko Peak soils do not have argillic horizons. Fruitland soils are sandy loam and free of gravel throughout the particle-size control section and do not have either argillic horizons or horizons of carbonate accumulation.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability in the solum, moderately rapid to rapid permeability in the 2C horizon; slow to medium runoff.
USE AND VEGETATION: These soils are used for rangeland or irrigated cropland. Crops are mainly alfalfa and small grains. Native vegetation is mainly Wyoming big sagebrush, Indian ricegrass, bottlebrush squirreltail, and galleta.
DISTRIBUTION AND EXTENT: Southwestern and south-central Utah. The series is moderately extensive. MLRA 28A and 28B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Beaver County, Utah, 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from the soil surface to a depth of 5 inches. (A horizon)
Argillic horizon: The zone of illuvial clay accumulation from a depth of 5 to 21 inches. (Bt horizons)
Calcic horizon: The zone of carbonate accumulation from a depth of about 21 to 30 inches. (Bk horizons)
Lithologic discontinuity: Strongly contrasting material occurs at a depth of about 30 inches. (2C horizon)
Particle-size control section: From the top of the argillic to a depth of 40 inches. (Bt, Bk, 2C horizons)
Classification changed from Xerollic Haplargids to Xeric Calciargids in 9/94.