LOCATION WAMPOO AZEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Argiduridic Durustolls
TYPICAL PEDON: Wampoo gravelly loam-rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; brown (7.5YR 4/3) gravelly loam, dark brown (7.5YR 3/2) moist; weak fine platy structure; slightly hard, very friable, slightly sticky, slightly plastic; many very fine and fine and few medium roots; few very fine vesicular and common very fine interstitial pores; 20 percent pebbles; neutral (pH 7.0); abrupt smooth boundary. (2 to 3 inches thick)
Bt1--3 to 5 inches; reddish brown (5YR 4/3) gravelly loam, dark reddish brown (5YR 3/2) moist; weak fine subangular blocky structure; slightly hard, friable, sticky and slightly plastic; many very fine, fine and common medium roots; many very fine and fine tubular pores; few thin clay films on faces of peds; 30 percent pebbles; neutral (pH 7.0); clear wavy boundary. (2 to 4 inches thick)
Bt2--5 to 8 inches; dark reddish gray (5YR 4/2) clay, dark reddish brown (5YR 3/2) moist; strong fine and medium prismatic structure parting to strong fine and medium angular blocky structure; very hard, firm, very sticky and very plastic; many very fine and fine and few medium roots; many very fine and fine tubular pores; many pressure faces; 5 percent pebbles; moderately alkaline (pH 8.0); clear wavy boundary. (3 to 4 inches thick)
Bt3--8 to 16 inches; reddish brown (2.5YR 4/4) clay, dark reddish brown (2.5YR 3/4) moist; strong fine and medium prismatic structure parting to strong fine and medium angular blocky; very hard, firm, very sticky and very plastic; many very fine, fine and few medium roots; many very fine and fine tubular pores; many pressure faces; 5 percent pebbles; moderately alkaline (pH 8.0); clear wavy boundary. (8 to 11 inches thick)
Btk1--16 to 2l inches; reddish brown (5YR 5/4) gravelly clay, reddish brown (5YR 4/4) moist; moderate fine and medium prismatic structure parting to moderate fine and medium subangular blocky; very hard, friable, very sticky and very plastic; few very fine roots; common very fine and fine tubular pores; many thin clay films in pores and on faces of peds; 25 percent pebbles; few very fine and fine soft lime masses and concretions; strongly effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (5 to 7 inches thick)
Bqkm--2l to 22 inches; pink (7.5YR 7/4) dry and brown (7.5YR 5/4) moist; indurated silica-lime cemented duripan with thin (l/8 inch) laminar surface; extremely hard; slightly effervescent. (1 to 4 inches thick)
Bqk--22 to 28 inches; pinkish white (7.5YR 8/2) dry and pinkish gray (7.5YR 7/2) moist; weakly cemented silica-lime horizon containing about 30 percent pebbles.
TYPE LOCATION: Greenlee County, Arizona; about l0 miles east of Apache Grove on Bitter Creek Road; l,600 feet east and 2,000 feet south of the NW corner of section 22, T. 6 S., R. 32 E.
RANGE IN CHARACTERISTICS:
Soil Depth: depth to the duripan ranges from 20 to 29 inches.
Soil moisture: Moisture control section is moist in some part in July-August and December-March. Epipedon is moist in some part more than 90 days (cumulative) in 7 out of 10 years. Ustic aridic moisture regime.
Soil temperature: The mean annual soil temperature ranges from 58 to 67 degrees F.
Organic matter: greater than one percent in the surface to l0 inches.
A horizon
Hue l0YR or 7.5YR
Value 4 or 3 dry, 3 or 2 moist
Chroma of 2 or 3
Texture is a gravelly loam or gravelly clay loam
Bt horizons
Hue 2.5YR or 5YR
Value 3 through 5 dry, 2 through 4 moist
Chroma of 2 through 4.
Texture is clay
The B2t horizon is slightly effervescent in some pedons
Btk horizon
Hue of 5YR or 7.5YR
Value of 4 or 5 dry, 3 or 4 moist
Chroma of 3 or 4
Texture is a clay, clay loam, or sandy clay loam with l5 to 30 percent pebbles
Calcium carbonate equivalent - 1 to 15 percent
Bqkm horizon
Hue of 7.5YR or l0YR
Value of 5 through 8 dry or moist
Chroma of 2 through 6.
It consists of a repeating indurated silica-lime cemented duripan l to 4 inches thick alternating with strongly silica and lime cemented sand, gravel, and cobbles
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Wampoo soils are on gently to moderately sloping old broad alluvial fans at elevations of 3,400 to 5,000 feet. Slopes range from 2 to 15 percent. These soils formed in mixed alluvium from dominantly volcanic sources. The climate is semiarid continental. The mean annual temperature ranges from 57 to 65 degrees F., and the average annual precipitation ranges from l2 to l6 inches. Precipitation occurs mainly as summer thundershowers and gentle winter rains. The frost-free season is l80 to 230 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Atascosa, Continental, Eba, Graham, Limpia, and Pinaleno soils. Atascosa and Graham soils are shallow over bedrock. Continental, Eba, Limpia, and Pinaleno soils lack a duripan. In addition, Eba, Limpia, and Pinaleno soils have greater than 35 percent coarse fragments in the control section.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; slow permeability.
USE AND VEGETATION: Used primarily as rangeland. Native vegetation includes tobosa, bush muhly, black grama, low-lying mesquite, juniper, pricklypear, burroweed, snakeweed, and fluffgrass.
DISTRIBUTION AND EXTENT: Southeastern Arizona. These soils are of small extent. MLRA 41.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Gila-Duncan Area, Greenlee County, Arizona; l978.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 8 inches thick. (A, Bt1, and Bt2 horizons)
Argillic horizon - the zone from 5 to 21 inches (Bt1, Bt2, and Btk horizons)
Duripan- the contact at 21 inches.
Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy Tenth Edition, 2006.
Classification changed in 1990 from Aridic Argiustolls to Aridic Durustolls. This subgroup was not available previously.