LOCATION AMENSON NMEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Petrocalcic Paleustolls
TYPICAL PEDON: Amenson loam--rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; brown (10YR 4/3) loam, dark brown (10YR 3/3) moist; moderate medium platy structure; slightly hard, friable, slightly sticky and slightly plastic; many medium and fine, few very fine roots; slightly alkaline (pH 7.6); clear smooth boundary. (2 to 4 inches thick)
Bt--3 to 11 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; strong medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and plastic; common very fine and fine roots; common moderately thick clay films on faces of peds and in pores; slightly effervescent, slightly alkaline (pH 7.6); clear smooth boundary. (4 to 14 inches thick)
Bk--11 to 15 inches; very pale brown (10YR 7/3) gravelly loam, brown (10YR 5/3) moist; weak coarse angular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; few very fine and very coarse roots; 20 percent coarse fragments mainly pieces of the petrocalcic horizon; violently effervescent; strongly alkaline (pH 8.6). (3 to 5 inches thick)
Bkm--15 to 19 inches; petrocalcic very pale brown (10YR 8/3) moist; massive; extremely hard; laminar; 91 percent calcium carbonate; no roots; violently effervescent; strongly alkaline.
TYPE LOCATION: Catron County, New Mexico, E. 1/2, NE 1/4 Sec. 11 T. 1 N., R. 17 W.
RANGE IN CHARACTERISTICS:
Depth to petrocalcic horizon: 6 to 20 inches
Soil moisture: Aridic ustic moisture regime
A horizon - Hue: 7.5YR or 10YR
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 2 or 3 dry or moist
Texture: loam or silty clay loam.
Bt horizon - Hue: 2.5Y or 10YR
Value: 3 through 5 dry, 3 or 4 moist
Chroma: 2 or 3 dry or moist
Texture: clay loam or sandy clay loam.
Bk horizon - Hue: 2.5Y or 10YR
Value: 3 through 7 dry, 3 through 6 moist
Chroma: 3 or 4 moist
Texture: sandy loam, silt loam with 10 to 25 percent gravel.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Amenson soils are developed in volcanic ash and alluvium on moderately undulating uplands with slopes of 1 to 9 percent. Elevation ranges from 6,800 to 7,800 feet. The mean annual precipitation is about 12 to 15 inches. The mean annual temperature is about 47 to 54 degrees F. The frost-free period is about 115 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Albinas, Capulin, Datil, Flugle, Ralphston, and Ruidoso soils. Albinas, Capulin, Datil, Flugle, Ralphston, and Ruidoso lack petrocalcic horizons and are deep.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used mainly for grazing. The native vegetation consists of blue grama, western wheatgrass, juniper, and pinyon.
DISTRIBUTION AND EXTENT: Catron County, central New Mexico, the soils are of small extent. MLRA 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Catron County, New Mexico, 1983.
REMARKS: DIAGNOSTIC HORIZONS AND FEATURES RECOGNIZED IN THIS PEDON ARE:
Mollic epipedon: The zone from 0 to 11 inches. (A and Bt horizons)
Argillic horizon: The zone from 3 to 11 inches. (Bt horizon)
Petrocalcic horizon: The very hard cemented pan at 15 inches.
ADDITIONAL DATA: Pedon #79NM-003-12 was sampled and sent to New Mexico State University for characterization.