LOCATION WILSON                  TX+OK

Established Series
Rev. CLN-RMR-RM
08/2017

WILSON SERIES


The Wilson series consists of very deep, moderately well drained, very slowly permeable soils that formed in calcareous clayey alluvium of Pleistocene age derived from mudstone. These nearly level to gently sloping soils are on treads of Pleistocene stream terraces. Slopes are mainly less than 1 percent but range from 0 to 5 percent. Mean annual precipitation is about 1003 mm (39.5 in) and the mean annual air temperature is about 18.1 degrees C (64.6 degrees F).

TAXONOMIC CLASS: Fine, smectitic, thermic Oxyaquic Vertic Haplustalfs

TYPICAL PEDON: Wilson silt loam in a Wilson silt loam, 0 to 1 percent slopes in cropland at an elevation of 122.9 m (403.2 ft). (Colors are for moist soil unless otherwise stated.)

Ap--0 to 13 cm (0 to 5 in); very dark gray (10YR 3/1) silt loam, gray (10YR 5/1) dry; weak fine granular structure when moist, massive when dry; very hard, firm; sticky and plastic; common fine roots; moderately acid; abrupt wavy boundary. (Thickness is 8 to 25 cm [3 to 10 in])

Bt--13 to 51 cm (5 to 20 in); very dark gray (10YR 3/1) silty clay, gray (10YR 5/1) dry; moderate medium angular blocky structure when moist; extremely hard, very firm; very sticky, very plastic; few fine roots; few fine pores; 25 percent, distinct, black 10YR 2/1 clay films on vertical faces of peds; 1, reversible trans-horizon crack; slightly acid; gradual wavy boundary. (Thickness is 25 to 51 cm [10 to 20 in])

Btkssgy1--51 to 81 cm (20 to 32 in); grayish brown (2.5Y 5/2) silty clay, light brownish gray (2.5Y 6/2) dry; moderate medium angular blocky structure when moist; extremely hard, very firm; very sticky, very plastic; few fine roots; few fine pores; 25 percent, distinct, slickensides; 25 percent, distinct, pressure faces; 25 percent, distinct, clay films on all faces of peds; 3, reversible trans-horizon cracks; 2 percent, fine, gypsum crystals; 2 percent, fine, calcium carbonate concretions; slightly alkaline; diffuse wavy boundary.

Btkssgy2--81 to 165 cm (32 to 65 in); grayish brown (2.5Y 5/2) silty clay, light brownish gray (2.5Y 6/2) dry; weak coarse angular blocky structure when moist; extremely hard, very firm; very sticky, very plastic; few fine roots; few fine pores; 25 percent, distinct, slickensides; 25 percent, faint clay films on all faces of peds; 4 percent, fine, gypsum crystals; 2 percent, fine, calcium carbonate masses; slightly alkaline; gradual smooth boundary. (Thickness of the Btkssgy horizons is 64 to 152 cm [25 to 60 in])

BCkss--165 to 203 cm (65 to 80 in); olive gray (5Y 5/2) silty clay, light gray (5Y 7/2) dry; weak coarse angular blocky structure when moist; extremely hard, very firm; very sticky, very plastic; few fine roots; few fine pores; 25 percent, distinct, slickensides; 2 percent, coarse, calcium carbonate masses; very slightly effervescent; moderately alkaline.

TYPE LOCATION: Kaufman County, Texas; from the intersection of Texas Highway 34 and U.S. Highway 175 in Kaufman, Texas, approximately 4 miles southeast on U.S. Highway 175, 0.15 miles northeast and 0.2 miles southeast of the intersection of a county road and U.S. Highway 175, and approximately 150 ft southwest into a field. Kaufman
USGS topographic quadrangle: Kaufman, TX;
Latitude: 32 degrees, 31 minutes, 11.467 seconds North;
Longitude: 96 degrees, 15 minutes, 56.321 seconds West.
Datum: WGS84

RANGE IN CHARACTERISTICS:
Soil Moisture: dry in some or all parts of the soil moisture control section, for 90 or more cumulative days and moist, in some part, either for more than 180 cumulative days per year, or for 90 or more consecutive days in normal years; ustic soil moisture regime that borders on udic
Soil depth: greater than 150 cm (greater than 60 in)
Depth to argillic horizon: 8 to 25 cm (3 to 10 in)
Depth to secondary calcium carbonate: 79 to 99 cm (31 to 39 in)
Depth to redox concentrations: 13 to 36 cm (5 to 14 in)
Depth to redox depletions: 13 to 203 cm (5 to 80 in)
Depth to salt accumulations: 150 to 203 cm (60 to 80 in)
Depth to gypsum accumulations: 58 to 203 cm (23 to 80 in)
Depth to reduced matrix: 13 to 91 cm (5 to 36 in)
Depth to slickensides: 13 to 66 cm (5 to 26 in)
Thickness of the ochric epipedon: 8 to 25 cm (3 to 10 in)
Surface fragments: amount-0 to 2, size-fine, medium, or coarse, kind-quartzite

Particle-size control section (weighted average)
Clay content: 35 to 50 percent
Rock fragments: 0 to 12 percent

A Horizon:
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 1 or 2
Texture: loam, silt loam, silty clay loam, clay loam, gravelly loam, gravelly silt loam, gravelly, silty clay loam, or gravelly clay loam
Clay content: 18 to 27 percent
Other Features: The A horizon is less than 25 cm (10 in) thick in more than 50 percent of the pedon, but it is as much as 38 cm (15 in) thick in some subsoil troughs. Some pedons have a thin E horizon in subsoil troughs.
Rock fragments: amount-0 to 35; size-fine, medium, or coarse; kind-quartzite or ironstone nodules
Effervescence: none
Reaction: moderately acid to neutral

Bt Horizon:
Hue: 10YR or 2.5Y
Value: 2 to 4
Chroma: 1
Texture: clay loam, silty clay loam, silty clay, or clay
Clay content: 27 to 45 percent
Clay films: amount-0 to 25 percent, distinctness-distinct or prominent; location-on vertical faces of peds and on all faces of peds
Redox concentrations: amount-0 to 20 percent, size-fine and medium, contrast-distinct or prominent, boundary-clear, shades-yellow or brown
Rock fragments: amount-0 to 15 percent; size-fine or medium, kind-quartzite
Electrical conductivity (decisiemens per meter): 0 to 4
Sodium Adsorption Ratio: 2 to 8
Effervescence: none to slightly
Reaction: slightly acid to slightly alkaline

Btss, Btgss, Btgssk, Btsskyg, Btgssy, Btkssy, or Btssy Horizon (where present):
Hue: 10YR to 5Y
Value: 3 to 7
Chroma: 1 or 2
Texture: silty clay, clay, silty clay loam, or clay loam
Clay content: 35 to 50 percent
Slickensides/Pressure faces: amount-5 to 50 percent; distinctness-faint, distinct, or prominent
Redox concentrations: amount-0 to 20 percent, size-fine to medium, contrast-faint, distinct, or prominent, boundary-clear or diffuse, shades-yellow, brown, or olive
Rock fragments: amount-0 to 15 percent; size-fine or medium, kind-quartzite
Identifiable secondary carbonate: amount-0 to 10 percent, size-fine or medium, kind-calcium carbonate concretions or calcium carbonate masses
Calcium carbonate equivalent: 1 to 20 percent
Gypsum: 0 to 4 percent
Electrical conductivity (decisiemens per meter): 0 to 8
Sodium Adsorption Ratio: 2 to 10
Effervescence: none to slight
Reaction: moderately acid to slightly alkaline

BCk or BC Horizon (where present):
Hue: 10YR to 5Y
Value: 4 to 6
Chroma: 1 to 4
Texture: clay loam, silty clay loam, silty clay, or clay
Clay content: 35 to 50 percent
Redox concentrations: amount-2 to 40 percent, size-fine to medium, contrast-faint, distinct, or prominent, boundary-clear or diffuse, shades- yellow, red or olive
Rock fragments: amount-0 to 15 percent; size-fine or medium, kind-quartzite
Pararock fragments: amount-0 to 35 percent; size-fine or medium; kind-claystone, siltstone, or mudstone
Identifiable secondary carbonate: amount-0 to 20 percent, size-fine or medium, kind-calcium carbonate masses, calcium carbonate concretions
Calcium carbonate equivalent: 1 to 20 percent
Gypsum: 2 to 15 percent
Electrical conductivity (decisiemens per meter): 2 to 8
Sodium Adsorption Ratio: 4 to 10
Effervescence: none to strong
Reaction: neutral to moderately alkaline

COMPETING SERIES: There are no competing series in the same family. Similar soils are the Lufkin and Mabank series.
Lufkin and Mabank soils: have an abrupt textural change between the A and Btg horizons

GEOGRAPHIC SETTING:
Parent material: calcareous clayey alluvium of Pleistocene age derived from mudstone
Landscape: Dissected Plains or River Valleys
Landform: tread on stream terraces
Slope: 0 to 5 percent
Mean annual precipitation: 813 to 1143 mm (32 to 45 in)
Thornthwaite P-E Index: 50 to 70
Mean annual air temperature: 15 to 22 degrees C (59 to 72 degrees F)
Frost-free period: 220 to 270 days
Elevation: 61 to 264.3 m (200.1 to 867.1 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bonham, Burleson, Crockett, Houston Black, Lufkin, Mabank, and Normangee series.
Bonham soils: have mollic epipedons and are on slightly higher positions.
Burleson and Houston Black soils: are clayey to the surface and have slickensides. In addition, Burleson soils are on similar positions and Houston Black soils are on slightly higher upland positions.
Crockett and Normangee soils: have Bt horizons with chroma of more than 2 and are on slightly higher positions.
Lufkin soils: are on high terraces or remnants of terraces
Mabank soils: have an abrupt textural change between the A horizon and Btg horizon and are on similar positions.

DRAINAGE AND PERMEABILITY:
Drainage class: Moderately well.
Permeability class:Very slow.
Runoff: high on 0 to 1 percent slopes and very high on 1 to 5 percent slopes. Very slow internal drainage.
Wetness: The soil is seasonally wet and is saturated in the surface layer and upper part of the Bt horizon during the winter and spring seasons for periods of 10 to 30 days.

USE AND VEGETATION: Used for cropland. Common crops are cotton, sorghum, small grains, and corn. Many previously cropped areas are now used for unimproved pasture. Native vegetation consists of little bluestem, yellow indiangrass, big bluestem, Texas wintergrass, vine mesquite, Florida paspalum, Virginia wildrye, silver bluestem, and sideoats grama and widely spaced motts of elm and oak trees. Most areas that are not cropped have few to many mesquite trees.

DISTRIBUTION AND EXTENT: North central, central, and South Central Texas; Land Resource Region J - Southwestern Prairies Cotton and Forage Region; Texas Blackland Prairies, Northern and Southern Parts (MLRAs 86A and 86B) and Texas Claypan Areas, Northern and Southern Part (MLRAs 87B and 87A); the series is extensive.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Temple, Texas

SERIES PROPOSED: Wilson County, Texas; 1907.

REMARKS: Classification change from Udertic Haplustalfs to Oxyaquic Vertic Haplustalfs based on knowledge that these soils are saturated for 2 to 4 weeks in most years. This period of time is within the definition of saturation for one month or more if rules of rounding are applied, i.e., 2 to 6 weeks saturation is considered inclusive.

Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 13 to 63 cm (5 to 25 in) (Bt1 and Btssgy1 horizons)
Ochric epipedon: 0 to 13 cm (0 to 5 in). The surface horizon is massive and hard or very hard when dry but is soft or friable when moist. (A horizon)
Argillic horizon: 13 to 165 cm (5 to 65 in). (Bt and Btkssgy1 horizons)
Slickensides: 51 to 203 cm (20 to 80 in). (Btkssgy1 and Btkssgy2 horizons)
Secondary gypsum: 51 to 165 cm (20 to 65 in). (Btkssgy1 and Btkssgy2 horizons)
Secondary carbonates: 51 to 203 cm (20 to 80 in). (Btkssgy1, Btkssgy2, and BCKss horizons)
Reduced matrix: 51 to 165 cm (20 to 65 in). (Btkssgy1 and Btkssgy2 horizons)
Vertic feature: When dry, cracks at least 6 mm (0.25 in) wide extend from the top of the argillic horizon through a thickness of 30 cm (12 in) or more within the upper 127 cm (50 in) of the soil.
Linear Extensibility: The linear extensibility is greater than 6 cm (2.5 in) within 102 cm (40 in) of the soil surface.
Coefficient of linear extensibility (COLE): 0.07 to 0.10 in the upper 127 cm (50 in) of the argillic horizon.
Other Features: The surface layer is variable in thickness with a series of micro crests and troughs in the Bt horizon that range from 1.2 to 6.1 m (4 to about 20 ft) apart. The soil does not have aquic soil conditions in the upper 51 cm (20 in) in most years.

ADDITIONAL DATA: Type location pedon KSSL S1962TX257001 Kaufman County, Texas, KSSL pedon S10TX2930015 from Limestone County, Texas, Texas A&M University pedon S09TX3090014 from McLennan County, Texas, Texas A&M University pedon S63TX-145-1, and Texas A&M University pedon S82TX-289-32.

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


National Cooperative Soil Survey
U.S.A.