LOCATION REDLIGHT TX

Established Series
JAC
10/2012

REDLIGHT SERIES

The Redlight series consists of very shallow and shallow, well drained soils formed in residuum and colluvium weathered from thick bedded limestone bedrock. Redlight soils are on hills and mountains. Slopes range from 5 to 65 percent. Mean annual air temperature is about 70 degrees F. (21 degrees C) and the mean annual precipitation is about 11 inches (279 mm).

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, hyperthermic Lithic Ustic Haplocalcids

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

A--0 to 7 inches, (0 to 18 cm); pale brown (10YR 6/3) very gravelly coarse sandy loam, brown (10YR 5/3) moist; 10 percent clay; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; common fine roots; 37 percent subangular mixed gravel; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (4 to 10 inches [10 to 25 cm] thick)

Bk--7 to 15 inches, (18 to 39 cm); very pale brown (10YR 7/4) very gravelly coarse sandy loam, light yellowish brown (10YR 6/4) moist; 11 percent clay; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common fine roots; 3 percent fine faint carbonate masses, 5 percent medium faint carbonate masses; 38 percent subangular mixed gravel; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (6 to 16 inches [15 to 41 cm] thick)

R--15 inches, (39 cm); indurated limestone bedrock.

TYPE LOCATION: Hudspeth County, Texas; from the intersection of Interstate Highway 10 and Laurel Street in Van Horn; 0.25 mile south on Laurel Street, continue south on Scott Crossing Road for 7.75 miles; 12.9 miles south on Green River Road; turn west on ranch road for 0.65 mile; and 395 feet south in rangeland. Lobo S.W., TX USGS 7.5 minute topographic quadrangle; Latitude 30 degrees, 46 minutes, 5.04 seconds North, Longitude 104 degrees, 56 minutes, 5.21 seconds West, NAD83; UTM easting: 506241 m, UTM northing 3403900 m, Zone 13.

RANGE IN CHARACTERISTICS:

Soil moisture: The driest period is November through April with peak rainfall occurring during May through October. Ustic aridic soil moisture regime.

Soil temperature: 72 to 78 degrees F. (22 to 26 degrees C)

Depth to lithic contact: 7 to 20 inches (25 to 50 cm)

Particle-size control section (weighted average)
Clay content: 8 to 15 percent
Rock fragment content: 35 to 85 percent

A horizon
Hue: 5YR, 7.5YR, 10YR
Value: 4 to 6, dry or moist
Chroma: 2 to 4, dry or moist
Texture: coarse sandy loam, sandy loam, loam, fine sandy loam, silt loam
Clay content: 8 to 15 percent
Effervescence class: strong or violent
Reaction: moderately alkaline

Bk horizon
Hue: 5YR, 7.5YR, 10YR
Value: 5 to 8 dry, 4 to 7 moist
Chroma: 2 to 4, dry or moist
Texture: coarse sandy loam, sandy loam, loam, fine sandy loam, silt loam
Clay content: 8 to 15 percent
Effervescence class: strong or violent
Reaction: moderately alkaline
Calcium carbonate equivalent: 15 to 35 percent

R layer
Kind: indurated limestone bedrock

COMPETING SERIES: This is the Redford (TX) series. Redford soils have 5 to 15 percent calcium carbonate equivalent, are on fan remnants and formed from fanglomerate.

GEOGRAPHIC SETTING: Redlight soils are on limestone hills and mountains at elevations of 3,000 to 4,000 feet (914 to 1,219 m). Slopes range from 5 to 65 percent. These soils formed in residuum and colluvium from limestone bedrock. The regolith consists of a thin mantle of loamy earth, containing many coarse fragments. The underlying rocks are thick bedded limestone. The mean annual precipitation is 10 to 13 inches (254 to 330 mm). The mean annual air temperature is 68 to 72 degrees F. (20 to 22 degrees C). The frost-free period is 240 to 280 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Corazones (TX), Ojinaga (TX) and Terlingua (TX) soils. Corazones soils are very deep and occur on alluvial fans, terraces, and piedmont slopes. Ojinaga soils have petrocalcic horizons and occur on alluvial fans, terraces, and piedmont slopes. Terlingua soils do not have a calcic horizon and occur on similar positions over igneous bedrock.

DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is low to medium on 5 to 10 percent slopes, medium on 10 to 20 percent slopes and high on 20 to 65 percent slopes. Permeability is moderately rapid to moderate over very slow.

USE AND VEGETATION: Used mostly for livestock grazing and wildlife habitat. Vegetation is mostly chino grama, black grama, creosote bush, ocotillo, prickly pear, candelilla, and leatherstem.

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

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

SERIES ESTABLISHED: Hudspeth County, Texas; Soil Survey of Hudspeth County, Texas (Main Part), 2012. The name Redlight is from the nearby Redlight Pass.

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

Ochric epipedon - the zone from 0 to 7 inches (0 to 18 cm) (A horizon)

Calcic horizon - the zone from 7 to 15 inches (18 to 38 cm) (Bk horizon)

Lithic contact - is the boundary at 15 inches (38 cm) (R horizon)

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

Revised for the correlation of Hudspeth County, Texas (Main Part) and Culberson County, Texas (Main Part); July, 2012, NMS

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

National Cooperative Soil Survey
U.S.A.