LOCATION HOWE TXEstablished Series
TAXONOMIC CLASS: Fine-silty, carbonatic, thermic Udic Haplustepts
TYPICAL PEDON: Howe silty clay loam--pasture. (Colors are for dry soil unless otherwise stated.)
A--0 to 7 inches; grayish brown (10YR 5/2) silty clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky and fine granular structure; hard, firm; common fine and medium roots; common wormcasts; few weakly cemented fragments of chalk that are less than 10 mm in diameter; calcium carbonate equivalent is about 60 percent; calcareous, moderately alkaline; gradual smooth boundary. (5 to 13 inches thick)
Bk1--7 to 15 inches; light gray (10YR 7/2) silty clay loam, light brownish gray (10YR 6/2) moist; moderate fine subangular blocky structure; hard, firm; common fine roots; common wormcasts; few weakly cemented fragments of chalk that are less than 5 mm in diameter; calcium carbonate equivalent about 60 percent; calcareous, moderately alkaline; gradual wavy boundary. (7 to 20 inches thick)
Bk2--15 to 26 inches; very pale brown (10YR 7/3) silty clay loam, pale brown (10YR 6/3) moist; moderate fine subangular blocky structure; hard, firm; few fine roots; about 27 percent weakly cemented platy fragments of chalk that are slightly hard dry, but break down on wetting and gentle rubbing; calcium carbonate equivalent about 60 percent; few threads and films of calcium carbonate; calcareous, moderately alkaline; gradual wavy boundary. (4 to 17 inches thick.)
Cr--26 to 32 inches; white (10YR 8/1) weakly cemented platy chalk with few thin seams of very pale brown silty clay loam in the upper part in vertical fractures and between plates of chalk; rock structure, distinct horizontal bedding; slightly hard to hard when dry, but can be easily cut with spade when moist; hardness less than about 2 on Mohs scale; calcareous, moderately alkaline.
TYPE LOCATION: Grayson County, Texas; from the intersection of U. S. Highway 82 and Texas Highway 11 in Sherman, Texas; 3.9 miles southeast on Texas Highway 11 to Luella; 0.1 mile west on paved county road; south 1.7 miles on paved county road to gate at the Holloway Cemetery; 25 feet west of road right-of-way in pasture.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 20 to 40 inches. Calcium carbonate equivalent of the control section ranges from 40 to about 80 percent. The texture of the soil is silty clay loam, silty clay or clay loam, with total clay content ranging from 30 to 45 percent and silicate clay content ranging from 25 to 35 percent.
The A horizon has colors with hue of 10YR, value of 4 to 6, and chroma of 2 or 3. Where moist values and chromas are less than 3.5, the A horizon is less than 7 inches thick. Fragments of weakly cemented chalk range from none to common.
The B horizons have colors with hue of 10YR or 2.5Y, value of 5 or 6, and chroma of 2 to 4. Some pedons have few to common yellow or brown mottles in the lower B horizon. The B horizons are silty clay loam, clay loam or silty clay. Pseudo rock fragments of chalk range from none to about 20 percent by volume in the upper B horizon and from about 5 percent 35 percent by volume in the lower B horizon. The fragments are hard to slightly hard when dry, but disintegrate upon overnight soaking in calgon and water. Platy fragments of calcite range from none to few.
The Cr horizon is white, light gray, very pale brown, or light brownish gray weakly cemented platy chalk or brittle marl. The upper few inches has thin seams of yellowish brown, brownish yellow, very pale brown, or pale yellow silty clay loam in fractures and between plates of chalk. The chalk becomes more massive and less fractured with depth. The chalk is easily cut with a spade when moist.
COMPETING SERIES: These include the Altoga and McLennan in the same family and the similar Austin, Brackett, Cuthand, Ellis, Lamar, Seawillow, and Whitewright series. Altoga, Lamar, McLennan and Seawillow soils lack a paralithic contact with chalk. In addition, Lamar soils have mixed mineralogy and Seawillow soils have fine-loamy control sections. Austin soils have mollic epipedons. Brackett and Whitewright soils have sola less than 20 inches thick. Cuthand soils have coarse-silty control sections. Ellis soils have COLE values of .09 or more and are noncalcareous.
GEOGRAPHIC SETTING: Howe soils are on upland ridges and upper sideslopes. Slope gradients are mostly 5 to 12 percent but range from 3 to 12 percent. The soil formed in weakly cemented marine chalk interbedded with marl, mainly of the Austin Group of Upper Cretaceous Age. Mean annual precipitation ranges from about 35 to 41 inches. The mean annual temperature ranges from 63 degrees to 66 degrees F. and the Thornthwaite P-E index ranges from 56 to 66.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Altoga, Austin, and Whitewright series and the Eddy, Fairlie and Lewisville series. Altoga and Lewisville soils are on lower lying stream terraces. Lewisville soils have mollic epipedons and lack a paralithic contact with chalk. Austin and Fairlie soils are on higher lying uplands. Fairlie soils have intersecting slickensides and wide cracks when dry. Eddy and Whitewright soils are in similar positions.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Used mostly for pasture. The main grasses are common and improved bermudagrass and K. R. bluestem. Native vegetation includes little bluestem, silver bluestem, sideoats grams, Texas wintergrass, threeawn with scattered elm and oak trees. A few areas are cultivated with cotton, small grain, and grain sorghum being the main crops grown.
DISTRIBUTION AND EXTENT: The Blackland Prairie of north-central Texas. The soil is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Grayson County, Texas; 1977.
REMARKS: Howe soils have formerly been included in the Austin series.
Classification was changed 11/89 from Typic Ustochrepts to Udic Ustochrepts.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 7 inches, the A horizon.
Cambic horizon - 7 to 26 inches the Bk horizon.
Paralithic contact of chalk at a depth of 26 inches.