LOCATION LOTT               TX

LOTT SERIES

TAXONOMIC CLASS: Fine-silty, carbonatic, thermic Udorthentic Haplustolls

TYPICAL PEDON: Lott silty clay--cropland. (Colors are for dry soil unless otherwise stated.)

Ap--0 to 5 inches; dark grayish brown (10YR 4/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate very fine and fine granular structure; slightly hard, friable; common fine roots; few fine pores; few fragments of snail shells; few fine rounded siliceous pebbles; calcareous, moderately alkaline; clear smooth boundary. (5 to 12 inches thick)

A--5 to 15 inches; dark grayish brown (10YR 4/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky and granular structure; hard, firm; common fine roots; common fine pores; calcium carbonate equivalent is 54 percent; few fine and medium fragments of chalk; few fragments of snail shell; few fine siliceous pebbles; calcareous; moderately alkaline; clear smooth boundary. (0 to 13 inches thick)

Bw--15 to 30 inches; brown (10YR 5/3) silty clay, dark brown (10YR 4/3) moist; moderate fine subangular blocky structure; hard, firm; few fine roots; few fine pores; calcium carbonate equivalent is 60 percent; few fine and medium fragments of chalk; few fragments of snail shell; few wormcasts; calcareous; moderately alkaline; clear smooth boundary. (4 to 19 inches thick)

Bk--30 to 47 inches; pale brown (10YR 6/3) silty clay, brown (10YR 5/3) moist; few fine faint very pale brown mottles; weak fine subangular blocky structure; hard, firm; few fine roots; common worm casts; calcium carbonate equivalent is 66 percent; common fine and medium fragments of chalk and soft masses of calcium carbonate; calcareous; moderately alkaline; clear smooth boundary. (8 to 20 inches thick)

Ck--47 to 80 inches; light gray (10YR 7/2), yellow (10YR 8/6) and white (10YR 8/1) clayey marl; massive to blocky, fractured; very hard and brittle, firm; few fine roots; many soft masses of calcium carbonate and few fine fragments of chalk in the upper part; calcareous; moderately alkaline.

TYPE LOCATION: Falls County, Texas; 7 miles east on Farm Road 2340 from its intersection with Texas Highway 6 in Perry; then 3.4 miles north on FM 2603, and 192 feet east in cultivated field.

RANGE IN CHARACTERISTICS: Solum thickness ranges from 40 to 60 inches. The calcium carbonate equivalent of the control section ranges from 40 to 80 percent. Texture is clay, silty clay, or silty clay loam throughout with 35 to 50 percent total clay and 25 to 35 percent silicate clay. Some pedons have a few chert pebbles on the surface and in the soil.

The A horizon has hue of 7.5YR or 10YR, value of 2 to 4, and chroma of 2 or 3.

The Bw horizon has hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 2 to 4.

The Bk horizon has hue of 10YR or 2.5Y, value of 6 to 8, and chroma of 3 to 6. Some pedons contain a few brownish, yellowish, or whitish streaks and mottles.

Colors of the Ck and C horizons are yellowish, brownish, light gray, or white. It is silty clay loam, silt loam, or clayey marl with or without fragments of chalk or limestone. The consistence is very hard and brittle when dry; however, the material slacks readily in water.

COMPETING SERIES: These include the Austin series in the same family and the Altoga, Bolar, Lewisville, Sunev, and Venus series. Austin soils have sola 20 to 40 inches thick over a paralithic contact with chalk. Altoga soils lack mollic epipedons. Bolar, Engle, Sunev, and Venus soils have fine-loamy control sections. Lewisville soils have mixed mineralogy.

GEOGRAPHIC SETTING: Lott soils are on gently sloping to moderately sloping stream divides and low ridges. Surfaces are usually convex and slopes range from 1 to 8 percent. The soil formed in calcareous clayey and marly soil materials of the Cretaceous Period mainly in the Ozan, Austin, and Grayson Geologic Formations. The climate is warm subhumid. Mean annual precipitation ranges from 32 to 37 inches; mean annual temperature from 65 degrees to 67 degrees F., and Thornthwaite P-E index from 50 to 64.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Austin series and the Heiden, Houston Black, Ponder, and Sanger series. Austin, Heiden, and Houston Black soils are on similar positions. Heiden and Houston Black soils have intersecting slickensides. Ponder and Sanger soils are typically on lower positions in the landscape. Ponder soils have a clayey argillic horizon and Sanger soils have intersecting slickensides.

DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderately slow permeability.

USE AND VEGETATION: Mostly cultivated to small grains, cotton, and grain sorghum. Original vegetation was mid and tall grasses such as little bluestem, indiangrass, and sideoats grama. Grasses now are mainly gramas and buffalograss.

DISTRIBUTION AND EXTENT: The Blackland Prairies of Texas. The series is of small extent.

MLRA OFFICE RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Falls County, Texas; l975.

REMARKS: The Lott series was formerly included in the Austin series.

Classification was changed 11/89 from fine-silty, carbonatic, thermic Entic Haplustolls to fine-silty, carbonatic, thermic Udorthentic Haplustolls.

Diagnostic features and horizons recognized in this pedon are:

Mollic epipedon - 0 to 30 inches.

Cambic horizon - 15 to 47 inches.

Carbonatic - > 40 percent calcium carbonate equivalent in control section.