LOCATION WHITEHILLS AZEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Typic Argidurids
TYPICAL PEDON: Whitehills very gravelly loam-rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 2 inches; yellowish brown (10YR 5/4) very gravelly loam, dark yellowish brown (10YR 3/4) moist; weak medium platy structure; slightly hard, friable, nonsticky and nonplastic, many very fine roots; many very fine vesicular pores; 40 percent gravel and 5 percent cobble; slightly effervescent; slightly alkaline (pH 7.8); clear wavy boundary. (1 to 2 inches thick)
Btk1--2 to 7 inches; strong brown (7.5YR 5/6) very gravelly loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine roots; common very fine tubular pores; common faint clay films on faces of peds; 35 percent gravel and 5 percent cobble; few fine soft calcium carbonate accumulations; slightly effervescent; 10 percent calcium carbonate equivalent; moderately alkaline (pH 8.0); clear wavy boundary. (5 to 14 inches thick)
Btk2--7 to 19 inches; strong brown (7.5YR 5/6) very gravelly clay loam, strong brown (7.5YR 4/6) moist; strong medium subangular blocky structure; very hard, firm, sticky and plastic; common very fine roots; common very fine tubular pores; strong distinct clay films on faces of peds; 40 percent gravel and 5 percent cobble; common fine soft calcium carbonate accumulations; strongly effervescent; 14 percent calcium carbonate equivalent; moderately alkaline (pH 8.0); abrupt wavy boundary. (8 to 15 inches thick)
Bk--19 to 27 inches; pink (7.5YR 8/4) very gravelly loam, pink (7.5YR 7/4) moist; massive; hard, firm, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; 45 percent gravel and 10 percent cobble with calcium carbonate coating undersides; many coarse soft calcium carbonate accumulations; violently effervescent; 24 percent calcium carbonate equivalent; moderately alkaline (pH 8.4); abrupt wavy boundary. (6 to 8 inches thick)
2Bkqm--27 inches; indurated silica-calcium carbonate cemented duripan.
TYPE LOCATION: Mohave County, Arizona; 1,200 feet east and 1,400 feet south of the northwest corner of Section 15, T. 20 N., R. 19 W. Gila and Salt River Base Meridian.
RANGE IN CHARACTERISTICS:
Soil Moisture: Intermittently moist in some part of the soil moisture control section during July-September and December- February. Driest during May and June.
Rock Fragments: 35 to 70 percent
Soil Temperature: 64 to 70 degrees F.
Organic matter: Less than 1 percent in the surface
Depth to duripan: 20 to 40 inches
Depth to unconsolidated alluvium: greater than 30 inches
A horizon
Hue: 7.5YR, 10YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 3 or 4, dry or moist
Bt horizon
Hue: 5YR, 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3, 4 or 6, dry or moist
Texture: loam, sandy clay loam, clay loam
Bk horizon
Hue: 7.5YR, 10YR
Value: 6, 7 or 8 dry, 4 through 7 moist
Chroma: 3 or 4, dry or moist
Texture: sandy loam, loam
COMPETING SERIES: This is the Deluge series. Deluge soils are 30 to 60 inches deep to conglomerate bedrock.
GEOGRAPHIC SETTING: Whitehills soils are on fan terraces and have slopes of 1 to 15 percent. They formed in fan alluvium from basalt, rhyolite, tuff and volcanic breccia. Elevations range from 2,000 to 4,800 feet. The mean annual precipitation is 6 to 12 inches. The mean annual air temperature is 62 to 68 degrees F. The frost-free period is 180 to 265 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Continental, Pajarito, and Tres Hermanos soils. These soils do not have a duripan.
DRAINAGE AND PERMEABILITY: Well drained. Medium to very high runoff. Moderately slow permeability.
USE AND VEGETATION: Whitehills soils are used for livestock grazing. The present vegetation is creosotebush, bursage, yucca, snakeweed, diamond cholla and annuals.
DISTRIBUTION AND EXTENT: Northwest Arizona. This series is not extensive. MLRA is 30.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Mohave County Area, Arizona, Central Part;
2005.
REMARKS: Diagnostic horizons and features recognized in this
pedon are:
Ochric epipedon - The zone from 0 to 2 inches (A
horizon)
Argillic horizon - The zone from 2 to 19 inches (Bt horizons)
Duripan - The zone of silica-calcium carbonate cementation at 27 inches (Bkqm horizon)
Classified according to Keys to Soil Taxonomy Ninth Edition, 2003.