LOCATION LULING TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Udic Haplusterts
TYPICAL PEDON: Luling clay - cropland. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 6 inches; dark grayish brown (10YR 4/2) clay, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; when dry the upper 2 inches form a mulch of very fine granules; extremely hard, extremely firm, very sticky and very plastic; many fine roots; cracks from 1/2 to 2 inches wide extend through the horizon; many worm casts; slightly alkaline; clear smooth boundary.
A--6 to 14 inches; dark grayish brown (10YR 4/2) clay, very dark grayish brown (10YR 3/2) moist; moderate fine and medium angular blocky structure with wedge-shaped peds; extremely hard, very firm, very sticky and very plastic; many fine roots; cracks from 1/2 to 1 1/2 inches wide extend through the horizon; many worm casts; slightly alkaline; gradual wavy boundary. (combined thickness of the A horizons 5 to 18 inches)
Bss1--14 to 30 inches; olive gray (5Y 5/2) clay, olive gray (5Y 4/2) moist; strong fine and medium angular blocky structure; extremely hard, very firm, very sticky and very plastic; peds are tilted above the horizontal; common fine roots; cracks from 1/2 to 1 inch wide extend through the horizon; common distinct slickensides; few very fine hard and pitted calcium carbonate concretions; slightly alkaline; gradual wavy boundary.
Bss2--30 to 42 inches; olive gray (5Y 5/2) clay, olive gray (5Y 4/2) moist; moderate medium angular blocky structure; peds are tilted above the horizontal; extremely hard, very firm, very sticky and very plastic; few fine roots; common distinct slickensides; few fine masses of calcium carbonate; common medium distinct brownish yellow (10YR 6/6) and olive (5Y 5/4) masses of iron accumulation; slightly alkaline; gradual wavy boundary. (combined thickness of Bss horizons 16 to 42 inches thick)
Bssy--42 to 54 inches; light olive gray (5Y 6/2) clay; olive gray (5Y 5/2) moist; weak medium angular blocky structure; extremely hard, very firm, very sticky and very plastic; few fine roots; common distinct intersecting slickensides; many gypsum crystals; few fine iron-manganese concretions; common medium distinct brownish yellow (10YR 6/6) masses of iron accumulation; common distinct streaks of darker materials that have filled old cracks; moderately alkaline; gradual wavy boundary. (0 to 22 inches thick)
Cy--54 to 70 inches; light gray (10YR 7/1) shale that has clay texture, gray (10YR 6/1) moist; massive; extremely hard, very firm, very sticky and very plastic; few fine roots; few fine iron-manganese concretions; many gypsum crystals; common medium prominent brown (7.5YR 5/4) and reddish yellow (7.5YR 6/8) masses of iron accumulation on surfaces of shale fragments; moderately alkaline.
TYPE LOCATION: Wilson County, Texas; 5.25 miles south of Stockdale on State Highway 123, 4.6 miles east on Farm Road 1347, and 150 feet south in field.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 50 to about 80 inches. Clay content of the control section ranges from 40 to 55 percent. Iron-manganese concretions range from none to few throughout, but are commonly in the lower part. Undisturbed areas have gilgai microrelief with microknolls 6 to 12 inches higher than microdepressions. Distance between the center of the microknoll and center of microdepression ranges from 4 to about 12 feet. The microknoll makes up about 20 percent, the intermediate, or area between the knoll and depression about 50 percent, and the depression about 30 percent. When dry, the soil has cracks 1/2 to 2 inches wide at the surface and commonly 1/2 inch wide cracks extend to a depth of more than 40 inches during the summer. The cracks remain open for more than 90 cumulative days during most years. Slickensides are at a depth 12 to 24 inches and extend throughout the solum. Reaction ranges from neutral to moderately alkaline. It is typically noncalcareous in the A horizon and calcareous or noncalcareous below.
In more than half of each pedon the A horizon has hue of 10YR to 5Y, value of 3 to 5 and chroma of 2 or 3 to a depth of at least 12 inches. Texture is clay or silty clay. The amplitude of waviness between the A and the Bss horizon is 5 to 18 inches.
The Bss horizon, or Bkss horizon where present, have hue of 10YR to 5Y, value of 4 to 6 and chroma of 2 to 4. Low chroma colors are lithochromic and not due to wetness. Texture is predominantly clay, but some pedons are silty clay. Redox concentrations in shades of brown, yellow, and olive range from none to common. Concretions and masses of calcium carbonates range from none to common.
The Bssy horizon, or Bkssy horizon where present, have colors in shades of brown, gray, yellow and olive. Texture is clay or silty clay. Crystals and masses of gypsum range from 2 to 25 percent. Reaction ranges from neutral to moderately alkaline. Some pedons contain few to common concretions and masses of calcium carbonate.
The C or Cy horizon has colors mainly in shades of gray, brown, yellow, or olive. It is weathered shale with clay texture or clay with interbedded fragments, strata, or spots of shale and/or thin strata of weakly consolidated sandstone. Crystals and masses of gypsum range from 2 to 25 percent. Calcium carbonate concretions or masses range from none to few. Some pedons contain a few siliceous or ironstone pebbles mainly less than 1/2 inch in diameter.
COMPETING SERIES: These include the Bleiblerville, Branyon, Burleson, Dimebox, Fairlie, Houston Black, Leson, Slidell, Heiden, Ovan, Sanger, and Tamford series. Bleiblerville, Branyon, Burleson, Dimebox, Fairlie, Houston Black, Leson and Slidell soils have chroma of 1 or less in the upper 12 inches of the surface in 50 percent or more of the pedon. Heiden, Ovan and Sanger soils are calcareous throughout. Tamford soils have red or reddish brown C horizons and annual air temperature of less than 65 degrees F.
GEOGRAPHIC SETTING: The Luling soils are on nearly level to moderately sloping erosional uplands. Slope gradients are 0 to 8 percent, but dominantly are 1 to 3 percent. The soils formed in alkaline shale mainly of the Cook Mountain Geologic Formation. Mean annual precipitation ranges from 30 to 40 inches, and mean annual temperature is 67 to 70 degrees F. Frost free days range from 260 to 280 days, and elevation ranges from 300 to 500 feet. Thornthwaite P-E index is 42 to 60.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Benchley, Crockett, Elmendorf, Marcelinas, Normangee, and Wilson soils. All of these soils have loamy surface layers and clayey argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is very slow. Water enters the soil rapidly when it is dry and cracked, and very slowly when it is moist and the cracks are closed. Runoff is low on slopes less than 1 percent, medium on 1 to 3 percent slopes, high on 3 to 5 percent slopes, and very high on 5 to 8 percent slopes.
USE AND VEGETATION: Most areas are cultivated; some areas are in rangeland. Cultivated crops are mostly cotton, corn, oats, wheat, and grain sorghum. Rangeland vegetation includes little bluestem, Indiangrass, twoflower trichloris, bristlegrass, sideoats grama, Texas wintergrass, mesquite, and hackberry.
DISTRIBUTION AND EXTENT: Southern Blackland Prairie of Texas (MLRA 86B). The soil is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Wilson County, Texas; 1972.
REMARKS: The series has been included with Heiden and Ferris series.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 14 inches. (A and Ap horizons)
Cambic horizon - 14 to 54 inches. (Bss horizons)
Vertisol feature - Intersecting slickensides between 14 to 54 inches. When dry cracks 1/2 inch wide or more range from the surface to a depth of more than 20 inches.
Soil Interpretation Record No.: TX0009