LOCATION MALOTERRE TXEstablished Series
TAXONOMIC CLASS: Loamy, carbonatic, thermic Lithic Ustorthents
TYPICAL PEDON: Maloterre gravelly clay loam--rangeland. (Colors are for dry soil unless otherwise stated.)
A1--0 to 8 inches; grayish brown (10YR 5/2) gravelly clay loam, dark grayish brown (10YR 4/2) moist; moderate fine subangular blocky and granular structure; hard, firm; contains 25 percent by volume of fragments of fine shell and limestone; a few fragments of limestone from 3 to 8 inches in diameter occur on the surface; moderately alkaline; calcareous; abrupt smooth boundary. (3 to 10 inches thick)
R--8 to 10 inches; indurated limestone containing many imbedded fossil shell, massive and unfractured, hardness of about 3 on Moh's scale.
TYPE LOCATION: Erath County, Texas; from the Erath County Courthouse in Stephenville, Texas, about 17 miles southeast on Texas Highway 67 to the intersection of Texas Highways 67 and 220; then 0.1 mile northwest on Texas Highway 67 and 60 feet north of highway fence in rangeland.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 3 to 10 inches. Total clay content ranges from 30 to 45 percent, with the noncarbonate clay fraction being less than 35 percent. Fragments, commonly of gravel size, of limestone in the soil range from 5 to 35 percent by volume. Calcium carbonate in the fraction less than 20 mm ranges from 40 to 80 percent.
The A horizon is dark grayish brown (10YR 4/2; 2.5Y 4/2), grayish brown (10YR 5/2; 2.5Y 5/2), brown (10YR 5/3, 4/3; 7.5YR 5/2, 4/2), light brownish gray (10YR 6/2; 2.5Y 6/2), pale or very pale brown (10YR 6/3, 7/3, 7/4). A horizons with moist color values and chromas of less than 3.5 are less than 4 inches thick. The A horizon is gravelly clay loam, gravelly clay, clay loam, or clay.
The R layer ranges from indurated white limestone to conglomerate limestone with many imbedded fossil shells.
COMPETING SERIES: These are the Brackett, Dugout, Ector, Eddy, Latom, Nebgen, Tarrant, and Yates series. Brackett and Dugout soils are deeper and have cambic horizons. Ector, Eddy, and Yates soils contain more than 35 percent coarse fragments. In addition, Ector soils have dark A horizons and Eddy, as well as Brackett soils, lack lithic contacts. Latom and Nebgen soils contain less than 40 percent calcium carbonate and have a lithic contact with sandstone. Tarrant soils have mollic epipedons, montmorillonitic mineralogy and contain more than 35 percent rock fragments.
GEOGRAPHIC SETTING: Maloterre soils occupy gently sloping to moderately steep, smooth to benched uplands with gradients ranging from 1 to 20 percent. The soil formed in residuum weathered from limestones of Lower Cretaceous Age. The localities of probable occurrence have mean annual temperatures of 64 degrees to 68 degrees F, range in average annual precipitation of 28 to 35 inches, and Thornthwaite annual P-E indices of 44 to 54.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Brackett and Dugout series and the Bolar, Denton, Purves, and Somervell series. Bolar, Denton, and Somervell soils have mollic epipedons and sola thicker than 20 inches. Purves soils have mollic epipedons and montmorillonitic mineralogy.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; rapid runoff; moderately slow permeability.
USE AND VEGETATION: Used as rangeland. Vegetation is mainly hairy tridens, a few forbs and some scattered midgrass plants. It is common for the surface to have less than 60 percent ground cover of any vegetation. Juniper is the main woody plant growing on this soil.
DISTRIBUTION AND EXTENT: Mainly in very shallow limestone areas of central and north-central Texas. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Parker County, Texas; 1973.
REMARKS: This update is a format update only. It was performed by the NSSQA staff on 8/89 because of previous storage problems at Ames, Iowa.
These soils formerly were classified as Lithosols and included in the Tarrant series.