LOCATION AFTADEN NMEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, thermic Lithic Haplargids
TYPICAL PEDON: Aftaden loamy sand--rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 2 inches; reddish brown (5YR 5/4) loamy sand, reddish brown (5YR 4/4) moist; single grain; loose when dry or moist, nonsticky and nonplastic; many very fine roots; many very fine interstitial pores; 5 percent basalt pebbles; neutral; abrupt smooth boundary. (1 to 4 inches thick)
Bt1--2 to 10 inches; reddish brown (5YR 5/4) fine sandy loam, reddish brown (5YR 4/4) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few fine and very fine roots; few fine tubular and many fine interstitial pores; clay bridging sand grains and few thin clay films on faces of peds; 5 percent basalt pebbles; neutral; clear smooth boundary. (4 to 10 inches thick)
Bt2--10 to 18 inches; reddish brown (5YR 5/4) fine sandy loam, reddish brown (5YR 5/4) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; common very fine tubular and many very fine interstitial pores; clay bridging sand grains and few thin clay films on faces of peds; 14 percent basalt pebbles; neutral; clear wavy boundary. (6 to 10 inches thick)
2R--18 inches; lime coated basalt rock.
TYPE LOCATION: Dona Ana County, New Mexico; NW 1/4 NW 1/4 Section 18, T. 26 S., R. 4 W.
RANGE IN CHARACTERISTICS:
Depth to bedrock - 10 to 20 inches.
Coarse fragments - 5 to 25 percent.
Surface cobbles - 0 to 35 percent.
Soil moisture Typic aridic moisture regime
A horizon
Hue: 7.5YR or 5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6
Texture: loamy sand or loamy fine sand.
Bt horizon
Hue: 7.5YR or 5YR
Value: 3 to 6 dry, and 3 to 5 moist
Chroma: 4 to 6
Texture: 7 to 18 percent clay, gravelly sand loam, gravelly fine sandy loam, sandy loam, or fine sandy loam.
COMPETING SERIES: These are the
Paradise Spring (CA),
Sparkhule (CA),
Stonegold (CA) and Zypler (NV) series.
Paradise Spring soils have 2.5Y or 10YR Hues and 20 to 30 percent clay in the argillic horizon.
Sparkhule soils have 25 to 35 percent clay in the particle size control section.
Stonegold soils have 15 to 25 percent clay in the particle size control section.
Zypler soils contain 20 to 30 percent clay in the particle size control section. In addition, all these soils are in MLRA 30 (Mohave Desert) receive mostly winter precipitation and are usually dry from April through November.
GEOGRAPHIC SETTING: The Aftaden soils formed in eolian sediments and material weathered from basalt. Aftaden soils are on uplands and have slopes of 1 to 15 percent. Elevation ranges from 4,000 to 5,000 feet. Mean annual temperature ranges from 59 degrees F. to 65 degrees F., and the mean annual precipitation is 8 to 10 inches. The frost-free period is 180 to 220 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Minlith and Onite soils. The Minlith soils lack a Bt horizon and are sandy-skeletal. The Onite soils are more than 60 inches deep.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately rapid permeability.
USE AND VEGETATION: Used mainly for rangeland. Native vegetation is mainly black grama, bush muhly, threeawn, and annuals.
DISTRIBUTION AND EXTENT: Southern New Mexico where it is moderately extensive. MLRA is 42.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Dona Ana County Area, New Mexico, 1977.
REMARKS:
Diagnostic horizon 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 18 inches. (Bt horizon)
Lithic contact: Bedrock at 18 inches.
Soil Taxonomy: Ninth Edition 2003