LOCATION NEBGEN TXEstablished Series
TAXONOMIC CLASS: Loamy, mixed, active, nonacid, thermic Lithic Ustorthents
TYPICAL PEDON: Nebgen sandy loam--rangeland. (Colors are for dry soil unless otherwise stated).
A1--0 to 5 inches; brown (7.5YR 4/4) sandy loam, dark brown (7.5YR 3/4) moist; moderate medium granular structure; slightly hard, friable; common fine roots; about 20 percent surface cover of sandstone fragments larger than 6 inches; 5 percent sandstone pebbles; slightly acid; clear smooth boundary. (4 to 10 inches thick)
A2--5 to 11 inches; brown (7.5YR 4/4) sandy loam, dark brown (7.5YR 3/4) moist; moderate medium granular structure; slightly hard, friable; common fine roots; 10 percent sandstone pebbles; slightly acid; abrupt smooth boundary. (0 to 8 inches thick)
R--11 to 15 inches; reddish brown indurated sandstone bedrock.
TYPE LOCATION: Llano, County, Texas. About 19 miles southwest of Llano, Texas. From the intersection of Texas Highway 16 and Ranch Road 2323 in Llano, 19.0 miles southwest of Llano on Ranch Road 2323, 0.6 mile east on private road, 50 feet east of road in rangeland.
RANGE IN CHARACTERISTICS: Solum thickness over sandstone is 4 to 14 inches. These soils are slightly acid or neutral throughout.
The A horizon has hue of 5YR, 7.5YR or 10YR, value of 3 to 6, and chroma of 3 to 6. Base saturation is more than 75 percent. The surface has 1 to 25 percent cover of sandstone cobbles and stones.
The R horizon is reddish or brownish sandstone, that has near horizontal bedding planes and is indurated. The sandstone or individual strata within the sandstone is calcareous in some pedons.
COMPETING SERIES: There are no competing series in the same family. Similar soils are the Darnell, Latom, and Yates series. Darnell soils have a cambic horizon. Yates soils have a loamy-skeletal control section over limestone. Latom soils are calcareous and dry in the moisture control section for longer periods.
GEOGRAPHIC SETTING: Nebgen soils are on undulating to steep uplands. Slopes range from 1 to 30 percent. The soil formed in strongly cemented sandstone mostly of the Hickory Formation but with some formed in Lion Mountain and Cap Mountain Formations. Mean annual precipitation ranges from 24 to 28 inches, and mean annual air temperature ranges from 65 to 68 degrees F. Frost free days range from 215 to 235 days, and elevation ranges from 1,000 to 2,200 feet. Thornthwaite annual P-E index ranges from 38 to 46.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the similar Yates as well as Campair, Hye, Loneoak, Matilo, Oben and Pontotoc soils. Campair, Hye, Loneoak, Matilo, Oben and Pontotoc soils have Bt horizons. In addition Campair, Hye, Loneoak, Matilo, and Pontotoc soils are more than 20 inches thick over sandstone, and Campair, Loneoak, and Matilo soils have sandy surface layers.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately rapid. Runoff is very low on 1 to 3 percent slopes, low on 3 to 5 percent slopes, medium on 5 to 20 percent slopes, and high on 20 to 30 percent slopes.
USE AND VEGETATION: Used for rangeland. Native vegetation includes sand lovegrass, hooded windmillgrass, threeawns, and little bluestem. Woody vegetation consists of persimmon, live oak, post oak, blackjack oak, whitebrush and catclaw.
DISTRIBUTION AND EXTENT: Texas and Oklahoma. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Gillespie County, Texas; 1970.
REMARKS: The soil classifies in the active cation exchange activity class. Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 11 inches. (A horizon)
Lithic contact - indurated sandstone bedrock at 11 inches.
Soil Interpretation Record No.: TX0044