LOCATION CHINATI TX

Established Series
NAR/LNK
10/2012

CHINATI SERIES

The Chinati series consists of very shallow and shallow, well drained soils that formed in gravelly alluvium and residuum derived from fanglomerate. Chinati soils occur on fan remnants. Slopes range from 1 to 30 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, shallow Petrocalcic Paleustolls

TYPICAL PEDON: Chinati very gravelly loam in rangeland. (Colors are for dry soil unless otherwise stated.)

A--0 to 3 inches; grayish brown (10YR 5/2), very gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky and weak thin platy structure; very friable, soft, nonsticky, and nonplastic; common very fine and fine roots; 35 percent igneous gravel and 5 percent igneous cobbles; very slightly effervescent; slightly alkaline; abrupt smooth boundary. (1 to 6 inches thick)

Bt--3 to 12 inches; dark brown (7.5YR 3/2), very gravelly loam, very dark brown (10YR 2/2) moist; moderate fine subangular blocky structure; friable, slightly hard, moderately sticky, moderately plastic; common very fine and fine roots; 10 percent distinct clay films on all faces of peds; 35 percent igneous gravel and 5 percent igneous cobbles; strongly effervescent; slightly alkaline; abrupt smooth boundary. (4 to 12 inches thick)

Bkkm--12 to 21 inches; white (7.5YR 8/1) cemented material, light gray (7.5YR 7/1) moist; moderately cemented by carbonates; very few very fine roots; 50 percent fine distinct platy moderately cemented carbonate masses with clear boundaries; 30 percent igneous gravel and 10 percent igneous cobbles; high excavation difficulty; violently effervescent; moderately alkaline; abrupt wavy boundary. (6 to 12 inches thick)

R--21 to 47 inches; brown (7.5YR 5/3) strongly cemented fanglomerate bedrock, brown (7.5YR 4/3) moist; very high excavation difficulty; violently effervescent; moderately alkaline.

TYPE LOCATION: Presidio County, Texas; from the intersection of County Road 2810 and U.S. Highway 90 in Marfa, TX; 22.6 miles southwest on County Road 2810 to ranch road; 1.9 miles southeast on ranch road; 63 feet southeast in rangeland. USGS Quadrangle: Oak Hills South, Texas. Latitude: 30 degrees, 8 minutes, 53.5 seconds N., Longitude: 104 degrees, 20 minutes, 46.7 seconds W.; NAD 83. UTM coordinates: Easting 562953 meters, Northing 3335386 meters, Zone 13.

RANGE IN CHARACTERISTICS:
Soil moisture: Aridic ustic moisture regime

Soil Temperature: 59 to 61 degrees F

Depth to bedrock: between 20 and 40 inches

Particle-size control section (weighted average)
Clay content: 18 to 35 percent
Rock fragments: more than 35 percent

A horizon
Hue: 5YR, 7.5YR, 10YR
Value: 3 to 5 dry, 2 to 3 moist
Chroma: 2 to 3, dry or moist
Texture: sandy loam, fine sandy loam, very fine sandy loam, loam, sandy clay loam, clay loam
Rock fragments: 30 to 70 percent
Effervescence: none to slight
Reaction: slightly alkaline

Bt horizon
Hue: 5YR, 7.5YR, 10YR
Value: 3 to 5 dry, 2 to 3 moist
Chroma: 2 to 3, dry or moist
Texture: loam, sandy clay loam, clay loam
Rock fragment: 35 to 75 percent
Effervescence: none to strong
Reaction: slightly alkaline

Btk horizon (where present)
Hue: 7.5YR, 10YR
Value: 3 to 5 dry, 2.5 to 4 moist
Chroma: 2 to 4, dry or moist
Texture: loam, sandy clay loam, clay loam
Rock fragment: 35 to 60 percent
Effervescence: strong to violent
Reaction: moderately alkaline

Bkkm horizon
Hue: 7.5YR, 10YR
Value: 8 dry, 7 to 8 moist
Chroma: 1 to 3, dry or moist
Cementation: weak to strong
Effervescence: violent
Reaction: moderately alkaline

R horizon
Hue: 5YR, 7.5YR, 10YR
Value: 5 to 8 dry, 4 to 8 moist
Chroma: 1 to 4, dry or moist
Cementation: strong or indurated

COMPETING SERIES: This is the Mierhill (TX) series. Mierhill soils do not have a lithic contact within 40 inches.

GEOGRAPHIC SETTING: Chinati soils are on fan remnants at elevations of 4,500 to 6,695 feet. Slopes range from 1 to 30 percent. These soils formed in gravelly alluvium and residuum derived from fanglomerate. The mean annual precipitation is 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 Brewster (TX), Boracho (TX), Marfa (T-TX), and Rockhouse (TX) series. Brewster and Boracho soils do not have an argillic horizon. Marfa soils are very deep and have more than 35 percent clay content in the particle-size control section. Rockhouse soils are in a sandy-skeletal textural family and occur in drainageways.

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability in the upper part and slow or very slow permeability in the petrocalcic horizon; runoff is low on slopes of 1 to 5 percent, medium on 5 to 20 percent, and high on 20 to 30 percent.

USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Mixed Prairie vegetative zone. Vegetation is mainly blue grama, black grama, sideoats grama, cholla, ephedra, javelina bush, sacahuista, sotol, and western honey mesquite.

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

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

SERIES ESTABLISHED: Presidio County, Texas; 2012. The name is from a mountain peak in Presidio County.

REMARKS: Diagnostic horizons and features recognized in this pedon are

Mollic epipedon - The zone from 0 to 12 inches (A and Bt horizons)

Argillic horizon - The zone from 3 to 12 inches (Bt horizon)

Petrocalcic horizon - The zone from 12 to 21 inches (Bkkm horizon)

Lithic contact - The zone from 21 to 47 inches (R horizon)

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.