LOCATION PAISANO TX+AZ

Established Series
Rev. RAC/JLR/ACT
10/2012

PAISANO SERIES

The Paisano series consists of soils that are very shallow or shallow to a petrocalcic horizon. They are well drained soils that are, moderately rapidly permeable above a very slowly permeable petrocalcic horizon. They formed in gravelly alluvium derived from mixed sources. These soils are on fan piedmonts and fan remnants. Slopes range from 1 to 12 percent.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, thermic, shallow Calcic Petrocalcids

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

A--0 to 3 inches; pale brown (10YR 6/3) very gravelly fine sandy loam, brown (10YR 4/3) moist; weak medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; 35 percent gravel from mixed sources; violently effervescent; moderately alkaline; abrupt smooth boundary (2 to 11 inches thick)

Bk--3 to 8 inches; light yellowish brown (10YR 6/4) very gravelly loam, dark yellowish brown (10YR 4/4) moist; weak medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many coatings of calcium carbonate on rock fragments; 45 percent gravel from mixed sources; violently effervescent; moderately alkaline; abrupt wavy boundary (5 to 9 inches thick)

Bkkm--8 to 28 inches; indurated caliche in the upper 9 inches and white strongly cemented caliche in the lower 11 inches; upper 1/4 to 1/2 inch is laminated; massive; violently effervescent; clear wavy boundary (4 to 25 inches thick)

BCk--28 to 80 inches; white (10YR 8/1) very gravelly sandy loam, weak medium granular structure; slightly hard, friable; 50 percent gravel from mixed sources; violently effervescent; moderately alkaline.

TYPE LOCATION: Brewster County, Texas: From the junction of U.S. Highways 90 and 385 in Marathon, Texas; 6.5 miles south on U.S. Highway 385 to ranch road; 2.4 miles southeast on ranch road; 60 feet west of road in range. Latitude: 30 degrees, 05 minutes, 31 seconds N; Longitude: 103 degrees, 13 minutes 44 seconds W.

RANGE IN CHARACTERISTICS:

Depth to the petrocalcic horizon: 6 to 20 inches

Coarse fragments: 35 to 85 percent. Fragments are mainly less than 3 inches in diameter, and are siliceous, sandstone, limestone and strongly cemented calcium carbonate pan fragments. Cobbles range from 0 to 15 percent

Calcium carbonate equivalent: 40 to 75 percent

Reaction: slight to moderately alkaline throughout

Mean annual soil temperature: 62 to 69 degrees F.

Soil moisture: Ustic aridic moisture regime

A and Bk horizons
Hue: 7.5YR, 10YR
Value: 4 to 8 dry, 2 to 6 moist
Chroma: 2 to 5, dry or moist
Texture: fine sandy loam, loam, sandy loam, sandy clay loam
Clay content: 5 to 25 percent

Bkm horizon
Induration: Continuous except for scattered cracks and pockets.

BCk horizon
Hue: 7.5YR, 10YR
Value: 5 to 8, dry or moist
Chroma: 2 to 4, dry or moist
Texture: sandy loam, loam, sandy clay loam, fine sandy loam
Coarse fragments: 35 to 60 percent by volume

COMPETING SERIES: These are the Ferrogold (NV), Infantry (I-NM), Neso (NM), Orrubo (AZ), Philder (NM), Sequite (NV), Sutherland (I-AZ), Tencee (NM), Wechech (NV) and Wodavar (NV) series. Infantry and Sutherland soils are inactive. Neso soils have mean annual soil temperatures of 59 to 62 degrees F. In addition, Neso soils are in the Pecos- Canadian Plains and Valleys (MLRA 70) and are moist in May and June. Orrubo soils have Cr horizons below the hardpan at depths between 17 and 30 inches. Ferrogold and Philder soils have petrocalcic horizons from 14 to 20 inches. Ferrogold, Orrubo, Sequite, Wechech, and Wodovar soils are in the Mohave Desert receive mostly winter precipitation and are usually dry from April through November. Tencee soils are drier in the control section for longer periods (typic/aridic). Wodavar soils have rock fragments that are mostly lime nodules and formed in lacustrine sediments.

GEOGRAPHIC SETTING: These soils are on fan remnants, and fan piedmonts. Slopes are mainly 1 to 5 percent but range to 20 percent on escarpments and sideslopes. Mean annual precipitation is 8 to 16 inches, and mean annual air temperature is 60 to 67 degrees F. Frost-free period is 180 to 260 days, and elevation ranges from 2,595 to 5,200 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Catto and Bullis series. Catto soils are shallow over chert bedrock and are on hills and mountains above. Bullis soils have argillic horizons, and are above and in similar positions.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately rapid above and below the slow or very slowly permeable petrocalcic horizon. Runoff is very low on 1 to 5 percent slopes and low on slopes 5 to 20 percent.

USE AND VEGETATION: These soils are used mainly for livestock grazing and wildlife habitat. Vegetation is blue grama, black grama, sideoats grama, bush muhly, threeawn, fluff grass, creosote bush, javelina bush, catclaw, and white thorn acacia.

DISTRIBUTION AND EXTENT: Southeastern Arizona and West Texas. MLRAs 41 and 42. The soil is of minor extent.

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

SERIES ESTABLISHED: Loving and Winkler Counties, Texas, 1994

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

Ochric epipedon - the zone form 0 to 3 inches (A horizon)

Petrocalcic horizon - the indurated layer is between 8 and 14 inches (Bkm horizon)

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

Update and revisions for recorrelation of Brewster County, Texas, Main Part, 2/12/08, CEM

This soil was previously included in the Tencee series.

Revised for the correlation of Big Bend National Park, TX, Oct. 2010 CEM

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

ADDITIONAL DATA: TAMU laboratory data No S90TX-043-004

National Cooperative Soil Survey
U.S.A.