LOCATION CONTINENTAL AZ+NMEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, thermic Vertic Calciargids
TYPICAL PEDON: Continental gravelly sandy loam-rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; brown (7.5YR 4/4) gravelly sandy loam, reddish brown (5YR 4/4) moist; weak thin platy structure parting to moderate fine and medium granular; slightly hard, very friable, nonsticky and nonplastic; many very fine and few fine roots; common fine and very fine irregular pores; neutral (pH 7.2); clear smooth boundary. (1 to 6 inches thick)
Bt1--3 to 8 inches; brown (7.5YR 4/4) clay loam, reddish brown (5YR 4/4) moist; weak fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine and few fine roots; few fine tubular and common fine irregular pores; common faint clay films on faces of peds and lining pores; slightly alkaline (pH 7.6); clear smooth boundary. (4 to 9 inches thick)
Bt2--8 to 15 inches, yellowish red (5YR 4/6) clay, yellowish red (5YR 4/6) moist; moderate fine and medium prismatic structure parting to moderate medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; common very fine and few fine roots; few fine tubular and common fine irregular pores; many faint clay films on faces of peds and lining pores; slightly alkaline (pH 7.8); clear wavy boundary. (5 to 10 inches thick)
Bt3--15 to 21 inches, brown (7.5YR 5/4) clay, brown (7.5YR 4/4) moist; weak fine prismatic structure parting to moderate medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; common faint clay films on faces of peds and lining pores; noneffervescent to slightly effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (6 to 12 inches thick)
Bk1--21 to 27 inches; light brown (7.5YR 6/4) clay loam, brown (7.5YR 4/4) moist; massive; very hard, friable, slightly sticky and slightly plastic; common very fine roots; few fine tubular and few fine irregular pores; violently effervescent; many fine and medium pinkish white 7.5YR 8/2) calcium carbonate accumulations and coatings; moderately alkaline (pH 8.2); abrupt wavy boundary. (6 to 15 inches thick)
2Bk2--27 to 60 inches, white (10YR 8/1) gravelly sandy loam, light gray (10YR 7/1) moist; massive; very hard, friable, nonsticky and nonplastic; few very fine roots; common fine tubular and common very fine irregular pores; violently effervescent; many medium and coarse pink (7.5YR 7/4) calcium carbonate accumulations; moderately alkaline (pH 8.4).
TYPE LOCATION: Yavapai County, Arizona; 1,050 feet north of the southwest corner of Section 22, t. 10 N., R. 6 W.
RANGE IN CHARACTERISTICS:
Soil Moisture: Usually dry, but is intermittently moist in some part of the moisture control section during July-September and December- February. Driest during May and June. Typic aridic soil moisture regime.
Rock Fragments: Less than 35 percent
Soil Temperature; Averages 59 to 72 degrees F.
Depth to calcic horizon: 20 to 40 inches. Calcium carbonate equivalent averages 15 to 25 percent.
A horizon
Hue: 5YR, 7.5YR
Value: 4, 5 or 6 dry, 3, 4 or 5 moist
Chroma: 3 through 6, dry or moist
Reaction: Slightly acid to moderately alkaline
Bt horizon
Hue: 2.5YR, 5YR, 7.5YR
Value: 3, 4, 5 or 6 dry, 3, 4 or 5 moist
Chroma: 4, 5 or 6 dry or moist
Texture: Clay, sandy clay, clay loam, sandy clay loam
Reaction: Slightly alkaline or moderately alkaline
Bk horizon
Hue: 5YR, 7.5YR
Value: 5, 6, 7 or 8 dry, 5, 6 or 7 moist
Chroma: 2, 3 or 4 dry, 3, 4, 5 or 6 moist
Texture: Clay loam, loam, sandy clay loam, sandy loam, fine sandy loam Reaction: Slightly alkaline or moderately alkaline
COMPETING SERIES: This is the Joveatch (NM) series. Joveatch soils are in the Desert Soil-Geomorphology Project, Las Cruces, New Mexico and have secondary accumulations of calcium carbonate in the lower part of the argillic and gypsum in the lower part of the profile.
GEOGRAPHIC SETTING: Continental soils are on fan terraces and have slopes of 0 to 15 percent. Elevations range from 1,000 to 5,000 feet. These soils formed in alluvium from dominantly acid igneous rock. The mean annual precipitation is 7 to 12 inches. The mean annual air temperature is 57 to 70 degrees F. The frost-free period is 180 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Comoro, Grabe, Mohave, Pima and Sonoita soils. Comoro, Grabe and Pima soils contain more than 1 percent organic matter. Mohave soils are fine-loamy. Sonoita soils are coarse-loamy.
DRAINAGE AND PERMEABILITY: Well drained. Low to high runoff. Slow permeability.
USE AND VEGETATION: Continental soils are used for grazing and irrigated cropland. The present vegetation is black grama, sideoats grama, tobosa, curly mesquite, false-mesquite, catclaw acacia and littleleaf paloverde.
DISTRIBUTION AND EXTENT: Southern Arizona and Southern New Mexico. MLRAs 40, 41 & 42. This series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Pima County (Tucson Area), Arizona; 1931.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 3 inches (A horizon)
Argillic horizon - The zone from 3 to 21 inches (Bt horizons)
Calcic horizon - The zone from 21 to 60 inches (Bk horizons)
Particle-size control section - the zone from 3 to 23 inches (The Bt horizon and part of the Bk1 horizon)
Vertic Subgroup: A linear extensibility of 6.0 cm or more between the soil surface and a depth of 100 cm
Classified according to Keys to Soil Taxonomy, Ninth Edition, 2003.
The classification was changed from fine, mixed, superactive, thermic Typic Haplargids to fine, mixed, superactive, thermic Vertic Calciargids in 2003.
The type location for this series has been moved. The first modern type location and series description dated 9-71 was found to be in a fine-loamy family. A second location and series description dated 3-83 was found to have an abrupt textural change and within the range of an existing series.
ADDITIONAL DATA: NSSL S68AZ023001 S68AZ023002