LOCATION ESPY TX+NM

Established Series
Rev. JLR/ACT
10/2012

ESPY SERIES

The Espy series consists of soils that are shallow to a petrocalcic horizon. They are well drained soils that are moderately permeable in the upper part and very slowly permeable in the petrocalcic horizon. These gently sloping soils formed in loamy and gravelly sediments from igneous sources. These soils are on fans and ridges in intermountain valleys. 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, mixed, superactive, thermic, shallow Petrocalcic Calciustolls

TYPICAL PEDON: Espy loam - rangeland. (Colors are for dry soil unless otherwise stated.)

A1--0 to 2 inches; grayish brown (10YR 5/2) gravelly loam; very dark grayish brown (10YR 3/2) moist; weak fine granular structure; slightly hard, very friable; common very fine and fine roots; 20 percent igneous gravel; violently effervescent; moderately alkaline; clear smooth boundary. (0 to 4 inches thick)

A2--2 to 9 inches; grayish brown (10YR 5/2) gravelly loam; very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, very friable; many very fine and fine roots; 25 percent igneous gravel; violently effervescent; moderately alkaline; clear smooth boundary. (6 to 16 inches thick)

Bk--9 to 14 inches; pinkish gray (7.5YR 6/2) gravelly loam; brown (7.5YR 4/2) moist; moderate fine granular structure; slightly hard, very friable; common very fine and fine roots; 25 percent igneous gravel; violently effervescent; moderately alkaline; abrupt wavy boundary. (4 to 10 inches thick)

Bkkm--14 to 26 inches; indurated petrocalcic; massive; extremely hard; laminar in the upper 1/8 to 1/2 inch; 20 percent igneous gravel imbedded; violently effervescent; moderately alkaline; clear wavy boundary. (4 to 20 inches thick)BCk--26 to 65 inches; light brown (7.5YR 6/4) gravelly fine sandy loam; brown (7.5YR 4/4) moist; single grain; slightly hard, very friable; 20 percent igneous gravel; violently effervescent.

TYPE LOCATION: Brewster, County, Texas; from the junction of U.S. Highway 90 and Texas Highway 118 in Alpine, 3.7 miles west on U.S. Highway 90, and 40 feet north of fence in rangeland. Alpine South,Texas USGS topographic quadrangle; Latitude: 30 degrees 20 minutes 25.77 seconds N; LongItude: 103 degrees 43 minutes 04.34 seconds W.

RANGE IN CHARACTERISTICS:
Soil moisture: aridic ustic moisture regime

Depth to a petrocalcic horizon: 10 to 20 inches

Particle size control section (weighted average)
Texture: loam, silt loam, or clay loam
Clay content: 18 to 30 percent
Rock fragment content: about 2 to 30 percent igneous and petrocalcic fragments.

A horizon
Hue: 7.5YR, 10YR
Value: 3 to 5, dry or moist
Chroma: 2 or 3, dry or moist
Texture: fine sandy loam, loam, clay loam
Reaction: slightly or moderately alkaline

Bk horizon
Hue: 7.5YR, 10YR
Value: 4 to 6, dry or moist
Chroma: 2 to 4, dry or moist
Texture; fine sandy loam, loam, clay loam
Reaction: slightly or moderately alkaline
Secondary carbonates: few to many in the form of films and threads

Bkkm horizon
Cementation: upper 1/4 to 2 inches is laminar, and the lower part is indurated to moderately cemented
Reaction: moderately alkaline

BCk horizon
Hue: 7.5YR, 10YR
Value: 6 to 8 dry, 4 or 5 moist
Chroma: 1 to 4, dry or moist
Texture: materials are commonly loamy, but are variable
Reaction: slightly or moderately alkaline
Rock fragment content: 15 to 60 percent

COMPETING SERIES: These are the Carbine (AZ), Kimberson (T)(TX), Ozona (TX), Pitzer (TX), and Queeny (TX) series. Carbine soils have petrocalcic horizons thicker than 20 inches and less than 18 percent clay. Kimberson, Ozona, Pitzer and Queeny soils are moist in the soil moisture control section in May and June and occur in the Great Plains. Kimberson soils formed in a thin mantle of loamy eolian sediments of the Blackwater Draw Formation of Pleistocene age and an underlying indurated caliche of Pliocene age. Ozona, Pitzer, and Queeny soils have mollic epipedons directly on indurated caliche. Queeny soils have unconsolidated material below the petrocalcic horizon.

GEOGRAPHIC SETTING: Espy soils are on fans and ridges in intermountain valleys. The soils are nearly level to gently sloping. Slopes range from 1 to 8 percent. The soils formed in loamy and gravelly sediments derived largely from areas of igneous rocks. Mean annual precipitation ranging from 12 to 25 inches and mean annual air temperature ranges from 59 to 66 degrees F. Frost free period range from 180 to 240 days, and elevation ranges from 4,500 to 6695 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Boracho, Brewster and Medley soils. Boracho soils are loamy-skeletal and are on similar landscapes. Brewster soils have sola less than 20 inches thick over consolidated volcanic bedrock and are on similar landscapes. Medley soils do not have a petrocalcic horizon and are in lower landscapes.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate in the upper part and slow or very slow in the petrocalcic horizon. Runoff is negligible on 1 percent slopes and low on 1 to 5 percent slopes.

USE AND VEGETATION: Used as rangeland for livestock grazing and wildlife habitat. Native vegetation is mostly black grama and blue grama grasses.

DISTRIBUTION AND EXTENT: West Texas and Southern New Mexico. MLRA 42. The series is of moderate extent.

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

SERIES ESTABLISHED: Jeff Davis County, Texas; 1971.

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

Mollic epipedon - the zone from 0 to 9 inches (A horizons)

Petrocalcic horizon - the zone from 14 to 26 inches (Bkkm horizon)

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

Type location was moved to Brewster County to better represent the series concept

Update and revisions for the recorrelation of Brewster County, Texas, Main Part, 2/8/08, CEM

Revised for the correlation of Presidio County, Texas ; Oct, 2012, WWJ
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National Cooperative Soil Survey
U.S.A.