LOCATION ELLEN TXEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, siliceous, active, thermic Aquic Arenic Paleustalfs
TYPICAL PEDON: Ellen gravelly loamy sand - rangeland.
(Colors are for dry soil unless otherwise stated.)
A--0 to 8 inches; pale brown (10YR 6/3) gravelly loamy sand, brown (10YR 5/3) moist; weak very fine granular structure; soft, very friable; common fine roots; rounded siliceous pebbles comprise 35 percent by volume; medium acid; clear smooth boundary. (6 to 18 inches thick)
E--8 to 28 inches; very pale brown (10YR 8/4) very gravelly loamy sand, very pale brown (10YR 7/4) moist; weak very fine granular structure; soft, very friable; few fine roots; rounded siliceous pebbles comprise 52 percent by volume; medium acid; clear wavy boundary. (14 to 32 inches thick)
Bt1--28 to 52 inches; white (10YR 8/1) very gravelly sandy clay loam, light gray (10YR 7/1) moist; common medium and coarse prominent dark red (10YR 3/6) mottles; weak fine and very fine subangular blocky structure; hard, firm, sticky, slightly plastic; contains about 5 percent by volume, red mottles; few fine roots; few pores; thin clay films on faces of peds and in pores; rounded siliceous pebbles, mostly 1 to 3 inches in diameter, comprise 51 percent by volume; extremely acid; gradual wavy boundary. (10 to 30 inches thick)
Bt2--52 to 76 inches; white (10YR 8/2) gravelly sandy clay loam, light gray (10YR 7/2) moist; many coarse prominent light brownish gray (10YR 6/2) and dark red (10YR 3/6) mottles; moderate fine and very fine subangular blocky structure; hard, firm, sticky, slightly plastic; contains about 10 percent by volume; red mottles; distinct thin clay films; rounded siliceous pebbles comprise 40 percent by volume and cobbles 10 percent by volume; very strongly acid; gradual wavy boundary. (14 to 26 inches thick)
C--76 to 84 inches; white (10YR 8/1) gravelly sandy clay loam, light gray (10YR 7/1) moist; common medium and coarse prominent red (2.5YR 4/8) mottles; massive; hard, firm, slightly sticky; rounded siliceous pebbles, mostly less than 1 inch in diameter, comprise 38 percent by volume; strongly acid.
TYPE LOCATION: DeWitt County, Texas; from the intersection of U. S. Highways 87 and 77A in Cuero, Texas; 4.8 miles southeast on U. S. Highway 87; then 2.8 miles northeast on a county road; 0.9 mile southeast on a private road to a turnoff; then 0.4 mile south and southeast to a gravel pit entrance; and 400 feet southwest along pit excavation border.
RANGE IN CHARACTERISTICS: The solum thickness ranges from 60 to 80 inches or more. Coarse fragments are mostly rounded siliceous pebbles and few cobbles range from 35 to 80 percent by volume in all horizons.
The A and E horizons are very gravelly sand, gravelly loamy sand or very gravelly loamy sand. They are slightly acid through strongly acid. The A horizon is brown (10YR 5/3; 7.5YR 5/2, 5/4), pale brown (10YR 6/3) or light brown (7.5YR 6/4). The E horizon is very pale brown (10YR 7/3, 8/4), light brown (7.5YR 6/4) or pink (7.5YR 7/4).
The Bt horizons are light gray (10YR 6/1, 7/1) or white (10YR 8/1, 8/2) mottles in shades of red, brown and other shades of gray. In some pedons the matrix is red or yellowish brown, mottled in shades of gray. Plinthite makes up 0 to 15 percent by volume of the Bt horizons. The Bt horizons are very gravelly or gravelly sandy clay loam, with an average clay content of the fine earth fraction ranging from 20 to 35 percent. They are strongly acid through extremely acid. Some pedons have loamy BC horizons, prominently mottled in shades of red, yellow and gray. Base saturation of the Bt horizons ranges from 35 to 60 percent by sum of cations.
COMPETING SERIES: There are no other series in the same family. Similar soils include the Nimrod, Silvern and Vernia series. Nimrod soils contain less than 35 percent by volume of coarse fragments in the Bt horizon. Silvern and Vernia soils have sandy epipedons more than 40 inches thick.
GEOGRAPHIC SETTINGS: Ellen soils are on gently sloping convex ridges. Slope gradients range from 1 to 3 percent, up to about 5 percent. The soil formed in ancient stream terrace or delta deposits of sand and gravel mainly associated with Citronelle geology. Mean annual temperature is 70 to 72 degrees F., average annual precipitation is 32 to 43 inches, and Thornthwaite annual P-E index is 42 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the similar Silvern soils and the Goldmire, Straber and Tremona soils. Silvern soils occur at slightly higher elevations. Goldmire, Straber and Tremona soils occur on similar surfaces. Goldmire and Straber soils have epipedons less than 20 inches thick. Tremona soils have less than 35 percent by volume of coarse fragments in the Bt horizon.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; moderately slow permeability; water drains rapidly from surface layers and is perched in thin layers from brief periods after rains in and above the Bt1 horizon.
USE AND VEGETATION: Used mostly as rangeland and mined locally for gravel materials. Native vegetation is mostly post oak, blackjack oak and mesquite trees with an understory of little bluestem, paspalums, panicums and lovegrass.
DISTRIBUTION AND EXTENT: Mainly in the southern part of the Texas Claypan area in south Texas. The soil is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: DeWitt County, Texas; 1973.
REMARKS: These soils would be in the Arenic Plinthaquic Paleustalfs subgroup, if a place was allowed for it in the Soil Taxonomy.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 28 inches.
Argillic horizon - 28 to 76 inches.
Arenic feature - sandy epipedon more than 20 inches thick.