LOCATION WASKOM TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, thermic Aquic Argiudolls
TYPICAL PEDON: Waskom loam--pasture.
(Colors are for moist soil unless otherwise stated.)
Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) loam;
moderate fine granular structure; hard, friable; many fine roots; slightly acid; clear smooth boundary. (5 to 14 inches thick)
A--7 to 15 inches; very dark grayish brown (10YR 3/2) loam; few
fine distinct reddish brown mottles; moderate fine granular structure; hard, friable; common fine roots; few earthworm channels; neutral; gradual smooth boundary. (5 to 16 inches thick)
Bt1--15 to 32 inches; dark brown (10YR 3/3) clay loam; few fine distinct reddish brown (5YR 4/4) mottles; common fine faint dark grayish brown (10YR 4/2) and common fine and medium distinct brown (10YR 4/3) mottles; moderate medium and coarse prismatic structure parting to weak medium subangular blocky; very hard, firm, slightly plastic; common fine roots; few fine pores; thin patchy clay films; few fine brown concretions; neutral; gradual smooth boundary. (10 to 20 inches thick)
Bt2--32 to 52 inches; mottled brown (10YR 5/3), yellowish brown
(10YR 5/6), and grayish brown (2.5Y 5/2) sandy clay loam; weak coarse prismatic structure parting to moderate fine and medium subangular blocky; very hard, firm, slightly plastic; few fine roots; few fine subangular mica flakes, neutral; gradual smooth boundary. (15 to 35 inches thick)
Bt3--52 to 80 inches; mottled yellowish brown (10YR 5/6), grayish brown (10YR 5/2; 2.5Y 5/2) and strong brown (7.5YR 5/6) sandy clay loam; weak coarse blocky structure; very hard, firm, slightly plastic; few fine roots; few strong brown concretions 2 to 4 mm in diameter with black interiors; neutral.
TYPE LOCATION: Red River County, Texas; north of Clarksville on Texas Highway 37 for 17.5 miles to Farm Road 195; west on Farm Road for 2 miles to Farm Road 410; northwest on Farm Road 410 for 11.5 miles; 1,300 feet south of road in field.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to more than 80 inches. The mollic epipedon is 20 to 40 inches thick, and includes part of the argillic horizon in most pedons.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3, and chroma of 2 or 3. Reddish or brownish mottles range from none to a few. It is loam, very fine sandy loam, or silt loam. The reaction ranges from medium acid to neutral.
The Btl horizon has hue of 7.5YR or 10YR, value of 2 or 3, and chroma of 2 or 3. Mottles in shades of brown ranges from few to common. It is loam, clay loam, or sandy clay loam with 20 to 35 percent clay and more than 20 percent silt in the upper 20 inches of the Bt horizon. The reaction ranges from slightly acid to mildly alkaline.
The lower Bt horizon is mottled mainly in shades of brown dominant hue of 10YR or 2.5Y with or without fine or medium reddish mottles. It is loam, clay loam, or sandy clay loam and the reaction ranges from slightly acid to mildly alkaline. Some pedons are moderately alkaline below a depth of 50 inches.
COMPETING SERIES: There are no other competing series in this family. Similar competing series are Bonham, Brewer, Garton, Muldrow, and Parisian. These soils have more than 35 percent clay in the control section. In addition, Brewer soils are dry in the moisture control section for longer periods of time and Parisian soils have vertic properties.
GEOGRAPHIC SETTING: Waskom soils are on nearly level stream terraces mainly along the Red River. Typically they are on the first terrace level. Slopes are less than 1 percent. The soils formed in alkaline alluvial sediments. The mean annual precipitation at the type location is about 45 inches; the mean annual temperature is about 64 degrees F., and the Thornthwaite annual P-E index is about 78.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gallion and Muldrow series. Gallion soils lack mollic epipedons and have higher chromas in the argillic horizon. Gallion soils are on slightly higher positions and Muldrow soils are below on slightly lower positions.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; moderately slow permeability. The water table is within 24 inches of the soil surface for brief periods during the cool season in most years.
USE AND VEGETATION: Most areas are used for cropland or tame pasture. Cotton, corn, grain sorghum, and soybeans are the principal crops. Native vegetation is cottonwood, sweetgum, ash, sycamore, elm, and pecan.
DISTRIBUTION AND EXTENT: Northeastern Texas, possibly Arkansas, Louisiana, and Oklahoma. This soil is of small extent.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 32 inches, the Ap, A and Bt1 horizons.
Argillic horizon - 15 to 80 inches, the Bt horizon.
Aquic feature - the soil has mottles with chroma of 2 or less at a depth of 15 inches.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED; Red River County, Texas; 1972.