LOCATION CASTLEDOME AZEstablished Series
TAXONOMIC CLASS: Clayey, mixed, superactive, thermic, shallow Aridic Haplustalfs
TYPICAL PEDON: Castledome fine sandy loam - rangeland. (Colors are for dry soil unless otherwise noted.) 5 to 15 percent of the surface is covered with gravel
A--0 to 1 inch; brown (7.5YR 4/4) fine sandy loam, dark brown (7.5YR 3/4) moist; moderate medium platy structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many fine irregular pores; noneffervescent; slightly alkaline (pH 7.6); clear smooth boundary. (1 to 3 inches thick)
Bt1--1 to 2 inches; dark reddish brown (5YR 3/3) clay loam, dark reddish brown (5YR 3/3) moist; weak very fine and fine subangular blocky structure; soft, very friable, moderately sticky and moderately plastic; common very fine roots; common very fine tubular pores; common distinct clay films on faces of peds and rock fragments; 3 percent gravel; noneffervescent; slightly alkaline (pH 7.6); abrupt smooth boundary.
Bt2--2 to 9 inches; dark reddish brown (2.5YR 3/4) clay, dark reddish brown (5YR 3/4) moist; strong very fine and fine subangular blocky structure; hard, firm, very sticky and very plastic; common fine and few medium roots; many very few fine tubular pores; many distinct clay films on faces of peds and rock fragments; 10 percent gravel; noneffervescent; slightly alkaline (pH 7.8); abrupt smooth boundary. (Combined thickness of the Bt horizons is 6 to 18 inches thick)
2Crtk--9 to 21 inches; fractured decomposed tuff; rigid; many distinct clay films and calcium carbonate coatings on rock fragments; common fine and few medium roots along fractures; violently effervescent; clear smooth boundary. (10 to 15 inches thick)
2Crk--21 to 34 inches; interbedded tuff and calcareous loam; extremely hard; many distinct calcium carbonate coatings on rock fragments; common fine roots along fractures and in the soil material; violently effervescent; abrupt smooth boundary. (10 to 15 inches thick)
2R--34 inches; unweathered tuff.
TYPE LOCATION: Cochise County, Arizona; located about 100 feet north and 1,400 feet east of the southwest corner of section 12, Township 21 S., Range 28 E.; Pedregosa Mountain West topographic map; latitude 31 degrees, 36 minutes, 44 seconds North and longitude 109 degrees, 27 minutes, 03 seconds West.
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. Aridic Ustic soil moisture regime.
Soil Temperature: 59 to 64 degrees F.
Reaction: slightly alkaline to moderately alkaline
Clay content: 35 to 50 percent
Organic matter: 0.5 to 2 percent
Depth to weathered bedrock: 7 to 20 inches
Depth to unweathered bedrock: 25 to 40 inches
A horizon
Hue: 10YR, 7.5YR
Value: 3 through 5 dry, 3 or 4 moist
Chroma: 3 or 4, dry or moist
Texture: fine sandy loam, sandy loam, loam
Bt horizon
Hue: 5YR, 2.5YR
Value: 3 through 5 dry, 3 or 4 moist
Chroma: 2 through 4, dry or moist
Texture: clay loam clay
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Castledome soils are on pediments at elevations of 4,600 to 6,200 feet. Slope ranges from 3 to 45 percent. These soils formed in slope and fan alluvium overlying tuff. The mean annual precipitation is 16 to 20 inches and occurs as thunderstorms during July to September and as gentle rains during December and January. The mean annual air temperature is 57 to 62 degrees F. The frost- free period is 160 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Denab, Cazador, Lesliecreek, Blacktail, Pyeatt, and Terrarossa soils. Denab soil has less than 35 percent clay over tuff. Cazador, Lesliecreek, Blacktail, Pyeatt, and Terrarossa soils are all very deep.
DRAINAGE AND PERMEABILITY: Well drained; medium to very high runoff; slow permeability.
USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Vegetation includes cane beardgrass, blue grama, sideoats grama, purple grama, Texas bluestem, shrubby buckwheat, oak, oneseed juniper, false mesquite, and plains lovegrass.
DISTRIBUTION AND EXTENT: Southern Arizona. MLRA is 41. Castledome soils are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Cochise County, Arizona; Soil Survey of Cochise County, Arizona, Douglas -Tombstone Part; 2000.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 1 inch (A horizon)
Argillic horizon - The zone from 1 to 9 inches (Bt1 and Bt2 horizons)
Paralithic contact - The boundary at 9 inches (2Crtk and 2Crk horizons)
Lithic contact - The boundary at 34 inches (2R horizon)
Soil Taxonomy Second Edition, 1999