LOCATION SET                     TX

Established Series
Rev. JDM-GLL-CLN-WJG
01/2017

SET SERIES

The Set series consists of deep, well drained, slowly permeable soils formed in clayey and loamy residuum derived from claystone bedrock of Pennsylvanian age. These very gently sloping to steep soils occur on ridges and escarpments of hills. Slope ranges from 1 to 40 percent. Mean annual precipitation is about 787 mm (31 in), and mean annual air temperature is about 17.8 degrees C (64 degrees F).

TAXONOMIC CLASS: Fine-silty, carbonatic, thermic Typic Calciustolls

TYPICAL PEDON: Set clay, extremely stony, on a convex 20 percent slope, in rangeland.
(Colors are for dry soil unless otherwise stated.)

A--0 to 30 cm (0 to 12 in); dark grayish brown (10YR 4/2) stony clay, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; hard, firm; many fine and few medium roots; about 25 percent of surface covered by fragments of limestone about 10 to 36 inches across and 3 to 8 inches thick; about 2 percent fragments of limestone 0.1 inch to 2 inches across; calcareous; moderately alkaline; clear smooth boundary. Thickness is 25 to 48 cm (10 to 19 in)

Bk1--30 to 66 cm (12 to 26 in); brown (10YR 5/3) gravelly clay, brown (10YR 4/3) moist; moderate fine and very fine subangular blocky structure; hard, firm; common fine and few medium roots; common fine pores; about 3 percent concretions and soft masses of calcium carbonate; about 20 percent fine limestone fragments less than 13 mm in diameter; about 2 percent limestone fragments 1 to 8 inches across; calcareous; moderately alkaline; gradual smooth boundary. Thickness is 25 to 51 cm (10 to 20 in)

Bk2--66 to 97 cm (26 to 38 in); yellowish brown (10YR 5/4) silty clay, dark yellowish brown (10YR 4/4) moist; moderate fine and very fine subangular blocky structure; very hard, firm; common fine and few medium roots; few fine pores; many concretions and soft masses of calcium carbonate; calcareous; moderately alkaline; gradual smooth boundary. Combined thickness of the Bk horizons is 51 to 102 cm (20 to 40 in)

BCk--97 to 112 cm (38 to 44 in); light yellowish brown (10YR 6/4) silty clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; very hard, firm; few fine and medium roots; few fine pores; many concretions and soft masses of calcium carbonate; calcareous; moderately alkaline; gradual wavy boundary. Thickness is 0 to 30 cm (0 to 12 in)

Cd--112 to 152 cm (44 to 60 in); light brownish gray (10YR 6/2) noncemented claystone bedrock and dense clay, grayish brown (10YR 5/2) moist; common streaks and mottles of light yellowish brown (10YR 6/4) and gray (10YR 6/1); material parts readily to medium angular fragments; few fine and medium roots in cracks; few concretions of calcium carbonate; calcareous; moderately alkaline.

TYPE LOCATION: Palo Pinto County, Texas; from the intersection of Texas Highways 16 and 108 in Strawn, 0.9 mile north on Texas Highway 16; 5.1 miles west on Farm Road 207; 1.2 miles north on county (Hohhertez) road and 15 feet east of road in rangeland.
USGS topographic quadrangle: Strawn West, Texas;
Latitude: 32 degrees, 36 minutes, 29.27 seconds N;
Longitude: 98 degrees, 34 minutes, 33.98 seconds W;
Datum: WGS84

RANGE IN CHARACTERISTICS:
Depth to densic bedrock: 102 and 152 cm (40 to 60 in)
Thickness of Mollic epipedon: 25 to 48 cm (10 to 19 in)
Depth to Calcic horizon: 25 to 76 cm (10 to 30 in)
Surface rock fragments: 0 to 40 percent dominantly stone size fragments
Reation (pH): moderately alkaline throughout (7.9 - 8.4

Particle-size control section (weighted average)
Total clay content: 35 to 55 percent
Silicate clay content: 20 to 35 percent
Calcium carbonate equivalent: 40 to 65 percent

A Horizon
Hue: 10YR to 2.5Y
Value: 3 to 5
Chroma: 2 to 3
Texture: clay, silty clay, silty clay loam, clay loam, or their stony counterparts
Calcium carbonate equivalent: 10 to 30 percent

Bk Horizon
Hue: 10YR to 5Y
Value: 5 to 6
Chroma: 2 to 4
Texture: clay, silty clay, or clay loam
Total clay content: 35 to 55 percent
Silicate clay content: 20 to 35 percent
Identifiable secondary carbonate: common to many, concretions and soft masses
Calcium carbonate equivalent: 40 to 65 percent

BCk Horizon (where present)
Hue: 10YR to 5Y
Value: 5 to 6
Chroma: 2 to 4
Texture: clay, silty clay, silty clay loam, or clay loam
Total clay content: 35 to 55 percent
Silicate clay content: 20 to 35 percent
Identifiable secondary carbonate: common to many, concretions and soft masses
Calcium carbonate equivalent: 40 to 65 percent

Cd Horizon
Colors: shades of olive, brown or gray
Texture: dense clay or claystone bedrock of Pennsylvanian age
Identifiable secondary carbonate: few to common in cracks, ped faces and pockets

COMPETING SERIES: There are no series in the same family. Closely similar soils are Bolar, Lewisville, Nuff, Nuvalde, Quanah, Somervell, and Venus series.
Lewisville and Quanah soils: have less than 35 percent total clay in the particle-size control section.
Nuvalde and Venus soils: have less than 40 percent carbonates in the particle-size control section.
Bolar soils: are underlain by limestone at depths of 20 to 40 inches.
Nuff soils: have sola 20 to 40 inches thick over claystone and are wetter for longer periods during growing season.
Somervell soils: contain more than 35 percent coarse fragments in the particle-size control section.

GEOGRAPHIC SETTING:
Parent material: loamy and/or clayey residuum weathered from claystone of Pennsylvanian age
Landscape: Hills
Landform: footslopes and backslopes of ridges and escarpments on hills
Slope: 1 to 40 percent
Mean annual precipitation: 660 to 864 mm (26 to 34 in)
Thornthwaite P-E Index: 40 to 50
Mean annual air temperature: 16.7 to 18.3 degrees C (62 to 65 degrees F)
Frost-free period: 210 to 240 days
Elevation: 243.8 to 548.6 m (800 to 1800 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hensley, Leeray, Owens, Palopinto, Thurber, and Truce series.
Hensley and Palopinto soils: occur on gently sloping limestone ridgetops.
Leeray soils: have gilgai micro-relief and occur below on broad nearly level and gently sloping footslopes and toeslopes.
Owens soils: have light colored surfaces, contain less calcium carbonate, and occupy positions similar to Set soils.
Thurber soils: are below along broad, nearly level to gently sloping valleys.
Truce soils: have light colored loamy surfaces and occur on lower footslopes positions.

DRAINAGE AND PERMEABILITY: Set soils are well drained. Permeability is slow. Runoff is high on 1 to 5 percent slopes and very high on slopes greater than 5 percent.

USE AND VEGETATION: Used for rangeland, but a few small gently sloping areas are cultivated to small grain or forage sorghum. Native grasses consist of sideoats grama, little bluestem, silver bluestem, buffalograss, and Texas needlegrass. Forbs include Maximilian sunflower, Engelmann-daisy, dalea species, and western ragweed. Sumac species, oak, elm, and whitebrush also occur.

DISTRIBUTION AND EXTENT: North-central Texas; LRR H - Central Great Plains Winter Wheat and Range Region, MLRA 80B - Texas north-central prairies; The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Palo Pinto County, Texas; 1979.

REMARKS:
Edited 01/2017 (RFG-SCP): Converted to tabular format and added metric units. Updated competing series, geographic setting, and associated soils sections.

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 30 cm (0 to 12 in) (A1 horizons).
Calcic horizon - 30 to 112 cm (12 to 44 in) (Bk1, Bk2 and BCk horizons).
Carbonatic mineralogy - the 25 to 100 cm control section contains more than 40 percent calcium carbonate equivalent.
Densic contact - 112 cm (44 in) top of cd layer.
Densic material - 112 to 203 cm (44 to 80 in) cd layer.

ADDITIONAL DATA: None

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014

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National Cooperative Soil Survey
U.S.A.