LOCATION LOMETA TXTentative Series
TAXONOMIC CLASS: Clayey-skeletal, mixed, active, thermic Typic Paleustalfs
TYPICAL PEDON: Lometa very gravelly sandy loam--on a north facing convex slope, in rangeland in post oak and blackjack oak, savannah. (Colors are for dry soil unless otherwise stated.)
A1--0 to 4 inches; pink (7.5YR 7/4) very gravelly sandy loam, brown (7.5YR 5/4) moist; weak fine granular structure; extremely hard, friable; many fine and medium roots; estimated 60 percent by volume of round siliceous pebbles from 2 mm to 75 mm in diameter; slightly acid; gradual smooth boundary. (3 to 8 inches thick)
A2--4 to 13 inches; pink (7.5YR 7/4) extremely gravelly sandy loam, brown (7.5YR 5/4) moist; weak fine granular structure; extremely hard; friable; common fine and medium roots; estimated 80 percent by volume of round siliceous pebbles from 2 mm to 25 mm in diameter; estimated 10 percent by volume of waterworn siliceous cobbles; slightly acid; abrupt smooth boundary. (6 to 13 inches thick)
Bt1--13 to 24 inches; red (2.5YR 4/6) very gravelly clay, dark red (2.5YR 3/6) moist; moderate medium blocky structure; very hard, firm, sticky and plastic; few fine roots; few clay films on faces of peds and on pebbles; estimated 50 percent by volume of round siliceous pebbles from 2 mm to 50 mm in diameter; slightly acid; gradual smooth boundary. (8 to 16 inches thick)
Bt2--24 to 38 inches; red (2.5YR 4/6) gravelly clay, dark red (2.5YR 3/6) moist; moderate medium blocky structure; very hard, very firm, sticky and plastic; few clay films on faces of peds and rock fragments; estimated 25 percent by volume of round siliceous pebbles from 2 mm to 50 mm in diameter; medium acid; gradual wavy boundary. (9 to 18 inches thick)
R--38 to 70 inches; strongly cemented conglomerate of round siliceous pebbles, cobbles and sand cemented with silica; slight effervescence.
TYPE LOCATION: Lampasas County, Texas; from the intersection of U. S. 190 and Ranch Road 581 in Lometa; southwest 4.2 miles on Ranch Road 581, then 1.4 miles southeast on ranch trail, then 30 feet south in range.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 20 to 40 inches. Coarse fragments of gravel size range from 25 to 80 percent by volume in individual horizons. The weighted average of the control section is 35 percent or more. Coarse fragments of cobble size range from 0 to 10 percent by volume. Depth to secondary carbonates is greater than 30 inches.
The A horizons have hue of 5YR or 7.5YR, value of 5 to 7 and chroma of 2 to 4. It is neutral or slightly acid, gravelly sandy loam, very gravelly sandy loam, or extremely gravelly sandy loam.
The Bt horizons have hue of 2.5YR, value of 3 to 5 and chroma of 4 to 8. It is neutral through medium acid. It is gravelly clay, very gravelly clay or extremely gravelly clay. The fine earth fraction contains 35 to 60 percent clay. Base saturation ranges from 75 to 100 percent.
The Bk horizon when present, is less than 10 inches thick and is reddish brown, reddish yellow, or yellowish red . It is slightly acid through moderately alkaline. It ranges from gravelly clay or extremely gravelly clay to gravelly sandy loam.
COMPETING SERIES: These include the Lusk series in the same family and the similar Chigley, Hilgrave, Hornsby, Pebblepoint, Pedernales, Riesel, Rumple, and Travis series. Lusk soils lack a lithic contact and have carbonates nearer the surface. Pebblepoint soils have sola more than 40 inches thick over chert. Chigley, Pedernales and Travis soils have less than 35 percent coarse fragments in the control section. Hilgrave and Hornsby soils have less than 35 percent clay in the fine earth fraction of the Bt horizon. Riesel soils have sola more than 40 inches over gravelly sediments.
GEOGRAPHIC SETTING: Lometa soils are on gently sloping to strongly sloping ancient stream terraces. Slope gradients range from 1 to 12 percent. The soil formed in a conglomerate of siliceous pebbles, cobbles and sand that is weakly to strongly cemented with silica like those of the Travis Peak formation. The source of the clay may not be entirely from the material. Mean annual temperature ranges from 64 degrees to 66 degrees F., mean annual precipitation of 26 to 30 inches and Thornthwaite P-E indices from 42 to 48.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Callahan, Cho, Eckrant, Nocken, and Real series. Callahan and Nocken soils are on similar and slightly lower positions. Callahan and Nocken soils are underlain by shale and sandstone. Cho soils are on slightly higher positions and are less than 20 inches deep with petrocalcic horizon. Eckrant and Real soils are less than 20 inches thick over limestone.
DRAINAGE AND PERMEABILITY: Well drained, runoff is medium; slow permeability.
USE AND VEGETATION: Used for rangeland. Native vegetation consists of little bluestem, sideoats grama, curly-mesquite, and buffalograss. Woody vegetation is post oak, blackjack oak, live oak, and kidneywood.
DISTRIBUTION AND EXTENT: Central Texas in the southern part of the North Central Prairie. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES PROPOSED: Lampasas County, Texas; 1980. The name is from a community in Lampasas County.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 13 inches.
Argillic horizon - 13 to 38 inches.
Lithic contact - 38 inches.
Paleustalf feature - abrupt textural change at 13 inches.