LOCATION KAUFMAN TX+AL AR OKEstablished Series
TAXONOMIC CLASS: Very-fine, smectitic, thermic Typic Hapluderts
TYPICAL PEDON: Kaufman clay--pasture. (Colors are for moist soil unless otherwise stated.)
A1--0 to 6 inches; black (10YR 2/1) clay; weak and moderate coarse angular blocky structure parting to moderate medium angular blocky; extremely hard, very firm, very sticky and very plastic; many fine roots; common very fine pores; few wormcasts; few pressure faces; slightly acid; diffuse smooth boundary.
A2--6 to 19 inches; black (10YR 2/1) clay; moderate fine and medium angular blocky structure; extremely hard, very firm, very sticky and very plastic; common fine roots and very fine pores; few pressure faces; slightly acid; diffuse wavy boundary. (combined A subhorizons 8 to 24 inches thick)
Bss1--19 to 35 inches; black (10YR 2/1) clay; moderate coarse angular blocky structure parting to moderate medium angular blocky; extremely hard, very firm, very sticky and very plastic; few fine roots and very fine pores; few fine distinct brown (10YR 4/3) redox concentrations or masses with sharp boundaries; common grooved slickensides; few iron-manganese concretions 2 to 4 mm in diameter; slightly acid; diffuse wavy boundary.
Bss2--35 to 50 inches; very dark gray (10YR 3/1) clay; moderate coarse angular blocky structure parting to moderate medium angular blocky; extremely hard, very firm, very sticky and very plastic; few fine roots mostly confined to surfaces of slickensides; few very fine pores; common fine distinct olive brown (2.5Y 4/3) and few fine distinct brown (10YR 4/3) redox concentrations or masses with sharp boundaries; many grooved slickensides; few iron-manganese concretions 2 to 4 mm in diameter; slightly acid; diffuse wavy boundary.
Bss3--50 to 69 inches; very dark gray (10YR 3/1) clay; moderate coarse angular blocky structure parting to moderate medium angular blocky; extremely hard, very firm, very sticky and very plastic; few fine roots mostly on faces of slickensides; few very fine pores; few fine distinct dark yellowish brown (10YR 4/4) redox concentrationsor masses with sharp boundaries; many grooved slickensides tilted at a 45 to 60 degree angle; few iron-manganese concretions 1 to 4 mm in diameter; slightly acid; diffuse wavy boundary.
Bss4--69 to 84 inches; very dark gray (10YR 3/1) clay; moderate coarse angular blocky structure parting to moderate medium angular blocky; extremely hard, very firm, very sticky and very plastic; many grooved slickensides tilted 25 to 45 degrees; few iron-manganese concretions 1 to 3 mm in diameter; slightly alkaline. (combined Bss subhorizons 58 to 72 inches thick
TYPE LOCATION: Delta County, Texas; about 4.6 miles east on State Highway 154 from Cooper, Texas, to its intersection with State Highway 19; 3.2 miles east and south on Highways 154 and 19 to the intersection of Farm Road 1536; 8.1 miles east and south on Farm Road 1536; to its intersection with Farm Road 71; 5.0 miles northeast on Farm Road 71 to its intersection with Farm Road 69; 2.6 miles north on Farm Road 69 and continuing on a county road to a bridge on the South Sulphur River; 0.65 mile north on private road and 50 feet west of the road.
RANGE IN CHARACTERISTICS: The solum is more than 80 inches thick. Depth of alluvial sediments ranges from 7 to about 35 feet. The reaction is moderately acid to moderately alkaline throughout. Some pedons are effervescent below a depth of 24 inches. The weighted average clay content of the control section ranges from 60 to 72 percent. Undisturbed areas have subdued gilgai microrelief, with microknolls 4 to 12 inches higher than microdepressions. Grooved slickensides begin at a depth of 10 to 24 inches. When dry cracks more than 1/2 of an inch wide extend to a depth of 20 inches or more for less than 90 cumulative days during most years. The redox concentrations or masses are considered to be mainly relic.
The A horizon has hue of 10YR, 2.5Y, or 5Y, value of 2 or 3, and chroma of 1 or less. Some pedons have redox concentrations in shades of brown, yellow, or olive in the lower part.
The Bss horizon has hue of 10YR, 2.5Y, or 5Y, value of 2 and chroma of 1 or less in the upper part and value of 3 to 5, and chroma of 1 or less in the lower part. In the lower part some pedons have chroma of 2 dominant in the matrix below a depth of 40 inches. Redox concentrations in shades of brown, yellow, or olive range from few to common. However, they are absent in some subhorizons. These concentrations or masses have sharp boundaries and are mainly relic features. Pitted calcium carbonate concretions range fom none to few.
COMPETING SERIES: These are the Billyhaw and Trinity series and the similar Eastham, Ganado, Tinn, Kaman and Zilaboy series. Billyhaw soils have chroma of 2 throughout. Eastham, Ganado, Kaman, Tinn, and Zilaboy soils have a fine textured control section. In addition Eastham soils are on terraces and typically do not flood. Ganado soils are hyperthermic. Kaman and Zilaboy soils are moist in the moisture control section for longer periods. Tinn and Trinity soils are calcareous throughout.
GEOGRAPHIC SETTING: Kaufman soils are on flood plains of streams draining Blackland Prairies. Slopes are mainly less than 1 percent; some are as much as 2 percent. The soil formed in clayey, alluvial sediments. Climate is warm-humid to moist subhumid. Mean annual precipitation ranges from 35 to 50 inches, and mean annual temperature ranges from 62 to 70 degrees F. Frost free days range from 230 to 280 days and elevation ranges from 100 to 550 feet. Annual Thornthwaite P-E indices exceed 50.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Trinity series and the Burleson, Catalpa, Crockett, Deport, Garner, Gladewater, Gowen, Heiden, Houston Black, Leson, and Wilson series. Burleson, Catalpa, Crockett, Deport, Garner, Heiden, Houston Black, Leson, and Wilson soils have fine textured control sections. Catalpa and Gowen soils have chroma of 2 or more in layers below the A horizon. In addition, Gowen soils are in a fine-loamy family. Gladewater soils are aquerts.
DRAINAGE AND PERMEABILITY: Moderately well drained. Permeability is very slow. Water enters the soil rapidly when it is dry and cracked and very slowly when it is wet. Runoff is low.
USE AND VEGETATION: Most cleared areas are in pasture of dallisgrass, bermudagrass, and fescues. A few areas are used for producing cotton, corn, sorghums, and soybeans. Native vegetation is hardwoods such as elm, hackberry, oak, ash, and grasses which includes species of andropogon, paspalum, panicum, and tripsacum.
DISTRIBUTION AND EXTENT: Flood plains of streams draining Blackland Prairies from Texas to Alabama. The series is extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Hunt County, Texas; 1934.
REMARKS: Series classification changed 2/94 based on new classification for Vertisols.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 19 inches (A1 and A2)
Cambic horizon - from 19 to 84 inches. (Bss1, Bss2, Bss3, and Bss4 horizons).
Vertisol features:
Grooved slickensides in horizons between 19 and 84 inches.
When dry there are deep wide cracks. The cracks are present for less than 90 cumulative days in most years.
ADDITIONAL DATA: Engineering Test Data prepared by the Texas Highway Department from type location.
SOIL INTERPRETATION RECORD NUMBERS: TX0441; TX1125 Frequently flooded; TX1188 Commonly flooded.