LOCATION CAVALRY TXEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Calciargids
TYPICAL PEDON: Cavalry loamy fine sand--rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 3 inches; brown (7.5YR 5/4) crushed, loamy fine sand, brown (7.5YR 4/4) crushed, moist; 6 percent clay; single grain; loose, loose, noncemented, nonsticky, nonplastic; few fine roots throughout; 5 percent nonflat rounded 0.1 to 1.0 inch mixed igneous fragments; slight effervescence, by HCl, 1 normal; moderately alkaline, pH 7.9, Phenol red; 2 percent calcium carbonate equivalent; abrupt smooth boundary. (2 to 6 inches thick)
Bt--3 to 14 inches; brown (7.5YR 5/4) crushed, fine sandy loam, brown (7.5YR 4/4) crushed, moist; 10 percent clay; weak coarse prismatic structure; very friable, soft, noncemented, nonsticky, nonplastic; few fine roots throughout; few fine tubular pores; 45 percent discontinuous distinct clay bridging between sand grains; 5 percent nonflat rounded 0.1 to 1.0 inch mixed igneous fragments; slight effervescence, by HCl, 1 normal; moderately alkaline, pH 8.0, Phenol red; 3 percent calcium carbonate equivalent; clear smooth boundary. (8 to 18 inches thick)
Btk--14 to 27 inches; brown (7.5YR 5/4) crushed, fine sandy loam, brown (7.5YR 4/4) crushed, moist; 12 percent clay; weak coarse prismatic structure; very friable, soft, noncemented, nonsticky, nonplastic; few fine roots throughout; few fine tubular pores; 45 percent discontinuous distinct clay bridging between sand grains; 3 percent fine irregular weakly cemented carbonate nodules throughout; 5 percent nonflat rounded 0.1 to 1.0 inch mixed igneous fragments; strong effervescence, by HCl, 1 normal; slightly alkaline, pH 7.6, Phenol red; 3 percent calcium carbonate equivalent; abrupt irregular boundary. (10 to 17 inches thick)
Bk1--27 to 48 inches; pink (7.5YR 7/3) crushed, fine sandy loam, pink (7.5YR 7/4) crushed, moist; 14 percent clay; moderate medium subangular blocky structure; friable, very hard, noncemented, slightly sticky, slightly plastic; few fine roots throughout; few fine tubular pores; 85 percent fine irregular carbonate masses throughout; 5 percent nonflat rounded 0.1 to 1.0 inch mixed igneous fragments; violent effervescence, by HCl, 1 normal; slightly alkaline, pH 7.8, Phenol red; 22 percent calcium carbonate equivalent; gradual smooth boundary. (15 to 32 inches thick)
Bk2--48 to 80 inches; pink (7.5YR 7/3) crushed, sandy clay loam, light brown (7.5YR 6/4) crushed, moist; 20 percent clay; moderate medium subangular blocky structure; friable, very hard, noncemented, slightly sticky, slightly plastic; few fine roots throughout; few fine tubular pores; 75 percent fine irregular carbonate masses throughout; 5 percent nonflat rounded 0.1 to 1.0 inches mixed igneous fragments; violent effervescence, by HCl, 1 normal; slightly alkaline, pH 7.8, Phenol red; 16 percent calcium carbonate equivalent.
TYPE LOCATION: El Paso County, Texas; approximately 1 mile northwest of Biggs Army Airfield. USGS El Paso topographic quadrangle; latitude 31 degrees 51 minutes 20.4 seconds north and longitude 106 degrees 23 minutes 48.03 seconds west. UTM zone 13, 367859E, 3525100N; NAD 27.
RANGE IN CHARACTERISTICS:
Soil Moisture: Typic aridic soil moisture regime. The moisture control section is usually dry in all parts more than three-fourths of the time that the soil temperature exceeds 41 degrees F.
Mean annual soil temperature: 63 to 67 degrees F.
Depth to calcic horizon: 20 to 40 inches
Particle-size control section (weighted average):
Clay content: 8 to 18 percent
Coarse fragment content: 0 to 10 percent
A horizon:
Value: 5 or 6, dry, 4 or 5 moist
Chroma: 2 to 4, dry or moist
Coarse fragments: mixed igneous fragments; 0 to 10 percent gravel size fragments
Clay content: 3 to 15 percent
Bt horizon
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 to 4, dry or moist
Coarse fragment: mixed igneous fragments; 0 to 10 percent gravel size fragments
Clay content: 8 to 18 percent
Btk horizon
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 to 4, dry or moist
Coarse fragment: mixed igneous fragment; 0 to 10 percent gravel size fragments
Clay content: 8 to 18 percent
Bk horizon
Value: 6 to 8 dry, 4 to 7 moist
Chroma: 1 to 4 dry, 2 to 4 moist
Texture: fine sandy loam, sandy clay loam, and loam
Clay content: 8 to 25 percent
Calcium carbonates equivalent: 15 to 40 percent
COMPETING SERIES: These are
Calcio (CA), Grapesumit (CA),
Onite (NM),
Patriot (NM), and
Yucca (NM).
The Calcio, Grapesumit, and Patriot soils have calcic horizons within 20 inches of the surface.
Onite soils have the base of the argillic horizon within 20 inches of the surface.
Yucca soils have an argillic horizon dominated by loamy sand.
GEOGRAPHIC SETTING:
Parent material: alluvium
Landform: alluvial flat on basin floor
Slope: 2 to 5 percent
Mean annual air temperature: 62 to 66 degrees F.
Mean annual precipitation: 8 to 10 inches
Precipitation pattern: precipitation falls mostly during the months of July through September. The driest months are March and April. Precipitation during the months of January, February, and March is less than 13 percent of the totals.
Frost-free period: 200 to 240 days
Elevation: 3,900 to 4,200 feet
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Copia,
Hueco,
Mcnew,
Patriot, and
Pendero soils.
Copia soils do not have calcic horizons and are on dunes.
Hueco soils are moderately deep to a petrocalcic horizon and are on similar positions.
Patriot soils have calcic horizons within 20 inches of the surface and are on similar positions.
Pendero soils do not have calcic horizons and are on sand sheets on basin floors.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is very low.
USE AND VEGETATION: Used for livestock grazing. Vegetation is of the desert shrub type consisting of creosotebush, fourwing saltbush, mesa dropseed, sand dropseed, bush muhly, plains bristlegrass, and black grama.
DISTRIBUTION AND EXTENT: Trans-Pecos of Texas and southern New Mexico; LRR D, MLRA 42; small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: El Paso County, Texas; 2001.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 3 to 23 inches. (Bt and Btk horizons)
Ochric epipedon: The zone from 0 to 7 inches. (A and Bt horizons, mixed)
Argillic horizon: The zone from 3 to 27 inches.
Calcic horizon: The zone from 27 to 80 inches. (Bk1 and Bk2 horizons)
The assignment of the cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.