LOCATION BENKLIN TXEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Aquic Argiudolls
TYPICAL PEDON: Benklin silt loam--idle cropland.
(Colors are for moist soils unless otherwise
stated.)
Ap--0-6 inches, very dark grayish brown (10YR 3/2) silt loam, moderate medium granular structure; hard, friable; many fine roots; few worm channels; neutral; abrupt smooth boundary. (5 to 18 inches thick)
Bt1--6-18 inches, very dark brown (10YR 2/2) loam; moderate very
fine and fine blocky structure; hard, friable; common fine roots; few fine pores; common wormcasts and channels; few patchy clay films; neutral; gradual smooth boundary. (6 to 17 inches thick)
Bt2--18-33 inches, very dark grayish brown (10YR 3/2) loam;
common medium faint dark grayish brown (10YR 4/2) and brown (10YR 4/3) mottles; moderate fine and medium blocky structure; hard, friable; common fine roots; few fine pores; common wormcasts and channels; few black concretions 1 to 2 mm in diameter; many peds have dark brown (10YR 2/2) clay films; neutral; gradual smooth boundary. (8 to 32 inches thick)
Bt3--33-41 inches, dark grayish brown (10YR 4/2) clay loam;
common medium faint brown (10YR 4/3) and yellowish brown (10YR 5/4) mottles; moderate medium prismatic structure parting to moderate fine and medium blocky structure; hard, friable; few fine roots; common wormcasts and channels; few black concretions 1 to 2 mm in diameter; very dark grayish brown (10YR 3/2) clayflows on faces of prisms; mildly alkaline; gradual smooth boundary. (4 to 22 inches thick)
Bt4--41-63 inches, mottled yellowish brown (10YR 5/4) and grayish brown (10YR 5/2) clay loam; few medium distinct yellowish brown (10YR 5/6) mottles; moderate medium prismatic structure parting to moderate medium blocky structure; hard, friable; few fine roots; common black concretions 2 to 4 mm in diameter; few black nodules; dark grayish brown (10YR 4/2) clay flows on faces of prisms; mildly alkaline.
TYPE LOCATION: Delta County, Texas; from the intersection of Farm Roads 38 and 128 in Ben Franklin, Texas, 0.8 mile east on Farm Road 128, 1.0 mile east on county road, 0.6 mile north; and 300 yards west.
RANGE IN CHARACTERISTICS: Solum thickness is more than 60 inches. Thickness of the mollic epipedon is 20 to 45 inches. The control section has 18 to 32 percent clay and 20 to 40 percent sand with less than 15 percent sand coarser than very fine sand.
The A horizon is very dark grayish brown (10YR 3/2), dark brown (10YR 3/3), or very dark brown (10YR 2/2) loam or silt loam. Reaction ranges from medium acid to neutral.
The Bt1 horizon is very dark brown or very dark grayish brown loam, silty clay loam, or clay loam. Reaction is slightly acid or neutral.
The Bt2 and Bt3 horizons have hue of 7.5YR or 10YR, value of 3 or 4, and chroma of 2 or 3. The texture is loam, silty clay loam, or clay loam. It contains few to many, faint or distinct mottles of dark grayish brown, grayish brown, brown, yellowish brown, dark yellowish brown, or strong brown. Reaction ranges from slightly acid to mildly alkaline.
The Bt4 horizon is loam, silty clay loam, or clay loam. It is typically mottled in shades of brown, yellow or red. Reaction ranges from neutral to moderately alkaline. Some pedons have a few pitted concretions of carbonate below a depth of 45 inches.
COMPETING SERIES: Competing series are the Armistead and Reelfoot in the same family and the similar Bonham, and Waskom series. Armistead soils have hues of 7.5YR or redder below the mollic epipedon. Bonham soils have a clayey control section. Reelfoot soils have a mollic epipedon 10 to 20 inches thick and have sola as thin as 30 inches. Waskom soils have a fine-loamy control section.
GEOGRAPHIC SETTING: Benklin soils are on nearly level to slightly concave terraces above overflow along major streams. Slope is 0 to 1 percent. Benklin soils formed in loamy alluvial sediments. The average annual precipitation ranges from 40 to 46 inches, the average annual temperature is about 63 degrees F., and the Thornthwaite P-E index is about 68.
GEOGRAPHICALLY ASSOCIATED SOILS: Associated soils are Caspiana, Kaufman, Muldrow, and Tinn series. Caspiana soils are well drained and do not have a water table in the upper 4 feet. Kaufman, Muldrow, and Tinn soils are more than 35 percent clay in the control section.
DRAINAGE AND PERMEABILITY: Benklin soils are somewhat poorly drained, have slow runoff, and have 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: Benklin soils are used mainly for growing cotton, grain sorghum, and soybeans. Many areas are in improved bermudagrass. Native vegetation is a mixed forest of elm, hackberry, oak, osage orange and pecan with an understory of Virginia wildrye, sedges and long leaf uniola, in open areas eastern gama bluestems and panicums are common.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
DISTRIBUTION AND EXTENT: These soils are mainly in the northeastern part of Texas. They are of small extent.
SERIES ESTABLISHED: Delta County, Texas; 1975.
REMARKS: These soils were formerly included in the Gowen series.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 33 inches, the Ap, Bt1 and Bt2 horizon
Argillic horizon - 6 to 63 inches, the Bt horizon.
Aquic feature - mottles immediately below the mollic epipedon and the layer is saturated at some period during the growing season.