LOCATION REAL               TX

REAL SERIES

The Real series consists of shallow, well drained, moderately permeable soils that formed in residuum over weakly to moderately cemented limestone. These soils are on gently sloping to steep uplands. Slopes range from 1 to 40 percent.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, thermic, shallow Typic Calciustolls

TYPICAL PEDON: Real gravelly clay loam--rangeland. (Colors are for dry soil unless otherwise stated.)

A--0 to 6 inches; dark grayish brown (10YR 4/2) gravelly clay loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to moderate fine granular; hard, friable; many very fine and fine roots; about 15 percent by volume weakly cemented limestone pebbles 0.2 inch to 2 inches in diameter, about 1 percent by volume cobbles and stones; thin 1/4 inch surface crust that is of slightly lighter color; violently effervescent; moderately alkaline; abrupt wavy boundary. (4 to 11 inches thick)

Ak--6 to 13 inches; dark grayish brown (10YR 4/2) extremely gravelly clay loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to moderate fine granular; hard, friable; many very fine and fine roots; about 75 percent by volume of weakly cemented limestone pebbles and caliche fragments from 0.2 inch to 3 inches in diameter; about 1 percent by volume cobbles and stones; violently effervescent; moderately alkaline; abrupt wavy boundary. (6 to 15 inches thick)

Cr--13 to 36 inches; weakly cemented white limestone chalk with the upper 1/2 to 1 inch moderately cemented; contains thin seams of light yellowish brown and brownish yellow material that is more pronounced with depth.

TYPE LOCATION: Uvalde County, Texas; From the intersection of U.S. Highway 90 and 83 in Uvalde 29.6 miles north on U.S. Highway 83 to a metal gate, 20 feet east and 50 feet south in rangeland in Garner State Park. (1927 NAD Latitude 29 degrees, 34 minutes, 32 seconds North; Longitude 99 degrees, 45 minutes, 3 seconds West.)

RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 8 to 20 inches, and corresponds to the depth to a paralithic contact of limestone chalk. Coarse fragments in the sola average from 35 to 85 percent and consists of limestone pebbles and caliche fragments mostly from 0.2 inch to 3 inches in diameter. The calcium carbonate equivalent is estimated to range from 40 to 70 percent in the fraction less than 2 cm.

The A horizon has hue of 7.5YR or 10YR, value of 3 to 5, and chroma of 1 to 3. The fine-earth fraction ranges from loam to clay loam with a silicate clay content of 22 to 35 percent. Carbonate clays range from a trace to about 6 percent. Secondary accumulations of calcium carbonate are soft bodies, cemented fragments and coatings that are mostly on the lower surfaces of limestone fragments.

The Cr horizon is weakly to moderately cemented limestone chalk that is interbedded with limy earth of loamy and clayey textures that is assumed to be partially secondary accumulations of calcium carbonate. In most pedons the upper 1/2 to 3 inches is bedrock plugged with cemented secondary carbonates but the continuity, crack spacing, and or thickness does not meet the requrements of a petrocalcic horizon.

COMPETING SERIES: Real is the only series in this family. Similar soils are the Aledo, Austin, Bolar, Brackett, Ector, Eddy, Eola, Patrick, Purves, Somervell, Stephen, Talpa, and Tarrant series. Austin, Bolar, and Somervell soils have sola more than 20 inches thick and have cambic horizons. Brackett and Eddy soils have ochric epipedons, and Brackett soils have cambic horizons. Aledo, Ector, Purves, Talpa, and Tarrant soils are underlain by stronly cemented or indurated. Eola soils have a petrocalcic horizon, precipitation of less than 26 inches, PE of less than 38, and occur on Edwards Marl. Patrick soils have clayey over sandy-skeletal control sections. Stephen soils have a clayey control section with less than 35 percent coarse fragments.

GEOGRAPHIC SETTING: Real soils are on gently sloping to steep uplands with surface gradients ranging from 1 to 40 percent. The soil formed in Cretaceous limestone and chalk that are interbedded with thin layers of marl and limestone. The climate is dry subhumid. Mean annual precipitation ranges from 26 to 34 inches. Thornwaite annual P-E index is 38 to 50. Frost free period is 220 to 250 days. Elevation ranges from 1000 to 2400 feet. The mean annual air temperature ranges from 65 to 70 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Aledo, Austin, Brackett, Ector, Eddy, Eola, Stephen, and Tarrant series, and Crawford, Kavett, Krum, Oplin, and Valera series. Aledo, Austin, Crawford, Kavett, and Valera soils occur at higher elevations and have less surface gradient. Crawford, Krum, and Valera soils have sola more than 20 inches thick and clayey control sections. Kavett soils have clayey control sections. Krum soils occur at lower elevations in valleys. Oplin soils are underlain by hard limestone and are on higher ridges. The other soils occur on similar surfaces.

DRAINAGE AND PERMEABILITY: Well drained. 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 40 percent slopes. Permeability is moderate.

USE AND VEGETATION: Used entirely as rangeland. Present grasses include sideoats grama, Texas wintergrass, tall grama, slim tridens, Hall panicum, fall witchgrass, red grama, and threeawn. Woody plants include juniper, live oak, Texas live oak, Texas persimmon, mescal bean, evergreen sumac, agarita, whitebrush, catclaw, and pricklypear cactus.

DISTRIBUTION AND EXTENT: Eastern Edwards Plateau and Grand Prairie resource areas of Texas, especially near the Balcones Fault Zone. Series is extensive with over a million acres.

MLRA OFFICE RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Uvalde County, Texas; 1970.

REMARKS: These soils were included with Tarrant soils which have a lithic contact of limestone. This series needs to be studied and redescribed to determine if the content of pararock fragments is such that the particle size class is loamy, rather than loamy-skeletal.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - 0 to 13 inches

Calcic horizon - 6 to 13 inches

Paralithic contact - at 13 inches