LOCATION ROXTON             TX
Established Series
Rev. DDR:CMT
02/2001

ROXTON SERIES

The Roxton series is a member of the fine, montmorillonitic,
thermic family of Vertic Haplaquolls. These clay soils have a
very dark gray A horizon, and a mottled, dark gray, dark yellowish brown, and strong brown B2g horizon over a very dark gray clay
loam Abg horizon.
TAXONOMIC CLASS: Fine, smectitic, thermic Vertic Epiaquolls

TYPICAL PEDON: Roxton clay--hardwood forest.
(Colors are for moist soils unless otherwise stated.)
A11 -- 0-13 inches, very dark gray (10YR 3/1) clay;
moderate fine and medium subangular blocky structure; extremely
hard, very firm, very sticky and plastic; few fine and medium
roots; few wormcasts; mildly alkaline; clear smooth boundary. (4
to 20 inches thick)
A12 -- 13-18 inches, very dark gray (10YR 3/1) clay; few medium distinct dark yellowish brown (10YR 3/4) mottles; moderate fine and medium subangular blocky structure; extremely hard, very firm, very sticky and plastic; few fine and medium tree roots; few wormcasts; few discontinuous dark grayish brown loamy strata 1 to
3 mm thick; mildly alkaline; gradual smooth boundary. (0 to 13 inches thick).
B21g -- 18-29 inches, dark gray (10YR 4/1) clay; common
medium distinct strong brown (7.5YR 5/6) and dark yellowish brown (10YR 3/4) mottles; moderate fine and medium blocky structure; extremely hard, very firm, sticky and plastic; common medium and large roots; few black concretions 1 to 3 mm in diameter; few pressure faces 1 cm across; neutral; gradual smooth boundary. (6
to 32 inches thick)
B22g -- 29-43 inches, mottled dark gray (10YR 4/1) and dark grayish brown (10YR 4/2) silty clay; common medium distinct dark yellowish brown (10YR 4/4) mottles; weak medium blocky structure parting to weak fine blocky structure; extremely hard, very firm, sticky and plastic; common fine, medium and large roots; few black concretions 1 to 3 mm in diameter; few black organic matter fragments; few thin lenses of brown loamy material; slightly acid; gradual smooth boundary. (12 to 32 inches thick)
ABG -- 43-64 inches, very dark gray (10YR 3/1) clay loam;
few fine distinct dark yellowish brown mottles; moderate medium blocky structure parting to weak fine blocky structure; extremely hard, very firm, sticky and plastic; common fine and medium roots; few black organic matter fragments; few black concretions 1 to 2
mm in diameter; few pressure faces 1 to 4 cm across; strongly
acid.
TYPE LOCATION: Lamar County, Texas; 13.7 miles northwest on Farm Road 79 from Northwest Loop 286 in Paris, and 200 feet north of
Farm Road 79 in Sanders Creek flood plain.
RANGE IN CHARACTERISTICS: Solum thickness is more than 60 inches. Thickness of the mollic epipedon ranges from 10 to 24 inches.
Most pedons contain a few black concretions.
The A horizon is black (10YR 2/1), very dark gray (10YR 3/1), or
very dark grayish brown (10YR 3/2; 2.5Y 3/2). The lower part of
the A horizon is commonly, distinctly, or prominently mottled dark reddish brown (5YR 3/3), yellowish brown (10YR 5/4), or dark yellowish brown (10YR 4/4, 3/4). The A horizon is clay loam,
silty clay, or clay. It ranges from neutral to moderately
alkaline. The A1 horizon is calcareous in the uppermost 10 inches
of some pedons.
The B2g horizon is dark gray (10YR 4/1; 5Y 4/1), gray (10YR 5/1), dark grayish brown (10YR 4/2), grayish brown (10YR 5/2), or light grayish brown (10YR 6/2) with common to many mottles of gray,
brown, and yellow. It is clay, silty clay, silty clay loam, or
clay loam. Between the depths of 10 and 40 inches the control section is 35 to 55 percent clay and less than 30 percent sand. Reaction of the B2g horizon ranges from strongly acid to mildly alkaline. Some part of the control section is medium acid,
slightly acid, or neutral. Some pedons have pockets and lenses of loamy material, but bedding planes have been destroyed.
Buried A horizons are common below a depth of 30 inches. They are dark gray (10YR 4/1) or very dark gray (10YR 3/1) with brown
mottles. Texture is clay loam, clay, or silty clay. Reaction
ranges from strongly acid through slightly acid.
COMPETING SERIES: Competing series are the
Gladewater, Griffith, Harris, Houlka, Iberia, Ijam, Kaman,
Kaufman, Leeper, Osage, Roellen, Terouge, and the Trinity series. Gladewater, Houlka, Ijam, and Leeper soils have no mollic
epipedon. Griffith, Kaman, Osage, and Terouge soils have a mollic epipedon thicker than 24 inches. Harris soils are saline and are saturated for 4 to 8 months in most years. Iberia soils have temperatures of about 68 degrees F., occur in areas of higher rainfall, and are wet for longer periods of time. Kaufman and Trinity soils have intersecting slickensides and very-fine
textured control sections. Roellen soils are in cooler climates. GEOGRAPHIC SETTING: These soils are in flood plains that have many scour channels and depressions. They formed in clayey and loamy
sediments, mainly from the Blackland Prairies. Slope is
dominantly less than 1 percent. The soils are frequently flooded October through May. The average annual precipitation at the type location is about 45 inches, the average annual temperature is 64 degrees F., and the Thornthwiate P-E index is about 67. GEOGRAPHICALLY ASSOCIATED SOILS: Associated soils are the competing Kaufman and Terouge series and the Ambia, Elbon, Lassiter,
Nahatche, and Pledger soils. Ambia soils have no mollic epipedon. Elbon soils have mixed mineralogy and are calcareous throughout. Lassiter and Nahatche soils are less than 35 percent clay in the control section. Pledger soils have redder hues in the lower part
of the B horizon.
DRAINAGE AND PERMEABILITY: Roxton soils are poorly drained, have very slow runoff, and have very slow permeability. They have a
water table within a depth of 24 inches of the surface from late October through May.
USE AND VEGETATION: These soils are used primarily for grazing. Improved pastures are such grasses as improved bermudagrass, dallisgrass, and fescue. Forested areas are mixed hardwoods dominated by water and willow oaks with an understory of sedges
and cool season grasses. Other trees are ash, elm, hackberry, locust, and osage orange.
DISTRIBUTION AND EXTENT: Roxton soils are mainly along the major streams that drain the Blackland Prairies in north-central Texas. They may be in south-central Oklahoma and in western Arkansas.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas


These soils are of small extent.
SERIES ESTABLISHED: Lamar County, Texas; 1975
REMARKS: These soils would have been classified in the Alluvial great soil group.
ADDITIONAL DATA: Particle-size distribution: Hydrometer method:
Sand
Silt Clay
13-18@ 4.6
38.0 57.4
18-29@ 12.6
34.0 53.4
29-43@ 14.4
40.2 45.4
National Cooperative Soil Survey
U. S. A.