LOCATION GROESBECK TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, superactive, thermic Udic Argiustolls
TYPICAL PEDON: Groesbeck loamy fine sand, on a north-facing, plane, 1 percent slope in rangeland at an elevation of 560 feet. (Colors are for moist soil unless otherwise stated.)
A--0 to 15 inches; very dark grayish brown (10YR 3/2) loamy fine sand, grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; slightly hard, very friable; common fine and medium roots; few fine pores; slightly acid; clear smooth boundary. (5 to 18 inches thick)
Bt--15 to 29 inches; light olive brown (2.5Y 5/4) sandy clay loam, yellowish brown (2.5Y 6/4) dry; few medium prominent brownish yellow (10YR 6/8) and strong brown (7.5YR 5/8) mottles; weak fine and medium subangular blocky structure; hard, firm; few fine and medium roots; few thin discontinuous clay films along root channels; few fine black concretions; few fine siliceous pebbles; neutral; clear smooth boundary. (7 to 24 inches thick)
Bk--29 to 32 inches; light brownish yellow (2.5Y 6/4) sandy clay loam, light brownish gray (2.5Y 6/2) dry; common medium prominent brownish yellow (10YR 6/8) mottles; moderate medium subangular blocky structure; hard, firm; few fine and medium roots; few fine and medium black concretions; common fine and medium calcium carbonate concretions; few coarse limestone fragments; few fine siliceous pebbles; slightly alkaline; abrupt wavy boundary. (0 to 13 inches thick)
2R--32 inches; hard fossiliferous limestone bedrock.
TYPE LOCATION: Limestone County, Texas; about 7 miles northwest of Groesbeck on Farm Road 1245; from the intersection of Farm Road 1245 and Farm Road 1633 in Thelma Community; 1 mile northwest on Farm Road 1245; north 1.8 miles on county road; 0.8 miles northeast on county road; 1600 feet south in rangeland. Latitude 31 degrees, 37 minutes, 25 seconds north; Longitude 96 degrees, 37 minutes, 29 seconds west.
RANGE IN CHARACTERISTICS: Solum thickness and depth to a lithic contact ranges from 20 to 40 inches. The mollic epipedon is 10 to 18 inches thick and in some pedons extends into the upper part of the Bt horizon. The lower boundary of the solum rests abruptly on limestone bedrock or grades into bedded limestone with soil occupying the interstices. The clay content of the particle-size control section ranges from 18 to 25 percent. Siliceous pebbles range from 0 to 5 percent throughout.
The A horizon has hue of 10YR, value of 2 to 5, and chroma of 2 or 3. Reaction ranges from slightly acid to neutral.
The Bt and/or Btk horizon has hue of 10YR, 2.5Y or 5Y, value of 3 to 7, and chroma of 2 to 8. Mottles are in shades of red, brown or yellow. Grayish colors are considered to be lithochromic. Texture is fine sandy loam, or sandy clay loam. Reaction ranges from slightly acid to slightly alkaline. Calcium carbonate concretions range from 0 to 15 percent. Black concretions range from none to few.
The Bk horizon has hue of 10YR, 2.5Y or 5Y, value of 5 to 7, and chroma of 2 to 6. Mottles are in shades of brown or yellow. Texture is fine sandy loam, loam, or sandy clay loam. Reaction is slightly alkaline or moderately alkaline. Calcium carbonate concretions range from 15 to 50 percent. Black concretions range from none to few. Limestone fragments range from none to few in the lower part of the horizon.
The 2R layer is hard limestone bedrock that is tightly fractured. Fossils range from none to common. Hardness is more than 3 on Moh`s scale.
COMPETING SERIES: These include the Coyle and Klump series in the same family. Similar soils are the Personville and Lavender series. Coyle soils do not have a lithic contact. Klump soils have redder hue and sola more than 40 inches thick. Lavender soils have a ochric epipedon, and Personville soils are deep to bedrock.
GEOGRAPHIC SETTING: Groesbeck soils are on nearly level to gently sloping uplands. Slope gradients are mainly less than 2 percent but range to 5 percent. These soils formed in loamy Pleistocene sediments deposited over the Tehuacana Limestone, mainly of the Midway Group of Tertiary Age. Mean annual precipitation ranges from 34 to 38 inches and the mean annual temperature ranges from 65 to 67 degrees F. Frost free days range from 250 to 260 and elevation ranges from 430 to 650 feet. Thornthwaite annual P-E indices range from 56 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Lavender, Personville, and Wilson soils. Lavender soils are on similar positions and have hue redder than 10YR in the Bt horizons. Personville soils are on similar to slightly higher positions and have a deep solum. Wilson soils are dark gray throughout and are on slightly lower positions.
DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff is low. Permeability is moderate.
USE AND VEGETATION: These soils are used mainly for improved pasture and native rangeland. Native vegetation is mainly tall prairie grasses.
DISTRIBUTION AND EXTENT: East Central Texas;(MLRA 86A). The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Limestone County, Texas; 1992. The name is from the town of Groesbeck.
REMARKS: Diagnostic horizon and features recognized in this pedons are.
Mollic epipedon - from 0 to 15 inches. (A horizon )
Argillic horizon - from a depth of 15 to 29 inches. (Bt horizon)
Lithic contact - hard limestone bedrock at 32 inches.
These soils were previously included with the Blum series
ADDITIONAL DATA: TAMU Soil Characterization Laboratory; S88TX-293-02. SNTC Soil Mechanics Laboratory; S88TX-293-02.