LOCATION CHILIMOL TX

Established Series
Rev. NAR
10/2012

CHILIMOL SERIES

The Chilimol series consists of very deep well drained soils that formed in calcareous gravelly alluvium derived from igneous rock. Chilimol soils occur on piedmont slopes and fan remnants. Slopes range from 1 to 8 percent. The mean annual precipitation is about 16 inches and the mean annual air temperature is about 60 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Aridic Calciustolls

TYPICAL PEDON: Chilimol very gravelly loam - rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 1 inch; brown (10YR 4/3) very gravelly loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; slightly hard, friable; 2 percent fine masses of calcium carbonate; 45 percent igneous gravel; violently effervescent; moderately alkaline; abrupt smooth boundary.

A2--1 to 10 inches; brown (10YR 4/3) very gravelly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable; 2 percent fine masses of calcium carbonate; 45 percent igneous gravel; violently effervescent; moderately alkaline; clear wavy boundary. (Combined thickness of the A horizons is 2 to 13 inches)

Bk1--10 to 22 inches; brown (7.5YR 5/4) very gravelly loam, brown (7.5YR 4/4) moist; weak medium subangular blocky structure; slightly hard, friable; 10 percent medium masses of calcium carbonate; 45 percent igneous gravel; violently effervescent; moderately alkaline; clear wavy boundary.

Bk2--22 to 48 inches; light brown (7.5YR 6/4) very gravelly loam, brown (7.5YR 5/4) moist; weak medium subangular blocky structure; slightly hard, friable; 20 percent medium masses of calcium carbonate; 40 percent igneous gravel; violently effervescent; moderately alkaline.

Bk3--48 to 65 inches; pink (7.5YR 7/4) very gravelly loam, light brown (7.5YR 6/4) moist; weak medium subangular blocky structure; slightly hard, friable; 20 percent medium masses of calcium carbonate; 40 percent igneous gravel; violently effervescent; moderately alkaline. (Combined thickness of the Bk horizons is 30 to more than 60 inches)

TYPE LOCATION: Presidio County, Texas; from the intersection of Washington Street and U.S. Highway 90 in Valentine, TX; west 0.9 mile on U.S. Highway 90 to ranch road; 1.6 miles west on ranch road; 1.0 mile south; 3.6 miles southwest; 7.0 miles south; 3,7 miles west to ranch headquarters; 0.9 mile southeast on ranch road; and 88 feet southwest in rangeland. Nancy Anne Ranch, TX USGS topographic quadrangle; Latitude: 30 degrees, 27 minutes, 48.58 seconds N.; Longitude: 104 degrees, 37 minutes, 5.61 seconds W., NAD 83; UTM Easting: 536649 m, UTM Northing: 3370208 m, Zone 13.

RANGE IN CHARACTERISTICS:
Soil moisture: Aridic ustic soil moisture regime

Soil temperature: 59 to 61 degrees F.
Thickness of mollic epipedon: 7 to 15 inches
Depth to calcic horizon: 7 to 31 inches
Reaction: moderately alkaline

Particle-size control section (weighted average):
Clay content: 15 to 32 percent
Rock fragments: 35 to 60 percent

A horizon
Hue: 10YR
Value: 3 to 5 dry, 2 to 3 moist
Chroma: 2 to 3, dry or moist
Texture: sandy loam, loam, silt loam
Rock fragments: 20 to 70 percent
Effervescence: strong to violent

Bw horizon (where present)
Hue: 10YR
Value: 4 to 5 dry, 2 to 4 moist
Chroma: 2 to 4, dry or moist
Texture: fine sandy loam, loam, silt loam
Rock fragments: 25 to 60 percent
Effervescence: strong to violent

Bk horizon
Hue: 7.5YR, 10YR
Value: 4 through 7 dry, 3 through 6 moist
Chroma: 2 through 6 dry, 3 through 6 moist
Texture: loam, silt loam, sandy clay loam, clay loam
Rock fragments: 15 to 75 percent
Effervescence: strong to violent

COMPETING SERIES: These are the Hathaway (AZ), Pinery (TX) and the Tascosa (TX) series. Hathaway soils average less than 20 percent clay content in the particle-size control section. Pinery soils formed in gravelly alluvial sediments from limestone sources, are slightly more moist in the soil moisture control section, and support pinyon, juniper, and oak. Tascosa soils are moist in the soil moisture control section during May and June and are typical of the Ogallala Formation in the Southern High Plains.

GEOGRAPHIC SETTING: Chilimol soils occur on piedmont slopes and fan remnants at elevations of 4,500 to 6,695 feet. Slopes range from 1 to 8 percent. These soils formed in calcareous gravelly alluvium derived from igneous rock. Mean annual precipitation ranges from 15 to 20 inches. Most precipitation occurs as high intensity rain during afternoon thunderstorms from June to September. The mean annual air temperature is 59 to 61 degrees F. The frost-free period is 180 to 220 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Berrend (TX), Boracho (TX), Espy (TX), and Murray (TX) soils. The Boracho and Espy soils have a petrocalcic horizon and occur on similar positions. The Berrend and Murray soils have less than 35 percent rock fragments in the particle-size control section and occur on similar positions.

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability, runoff is low on slopes 1 to 5 percent and medium on 5 to 8 percent.

USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Mixed Prairie vegetative zone. Vegetation includes creosotebush, tarbush, littleleaf sumac, ephedra, Spanish dagger, tasajillo, broom snakeweed, black grama, spike dropseed, sand dropseed, bush muhly, and fluff grass.

DISTRIBUTION AND EXTENT: West Texas. MLRA 42. This series is of minor extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Presidio County, Texas; 2012.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - The zone from 0 to 10 inches (A1, A2 horizons)

Calcic horizon - The zone from 10 to 65 inches (BK1, Bk2, BK3 horizons)

Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Eleventh Edition, 2010

Revised for the correlation of Presidio County, Texas ; Oct, 2012, WWJ

National Cooperative Soil Survey
U.S.A.