LOCATION ELMENDORF TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, hyperthermic Vertic Argiustolls
TYPICAL PEDON: Elmendorf clay loam--cultivated. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 6 inches; dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; hard, friable; common roots; noncalcareous; mildly alkaline; abrupt smooth boundary. (4 to 10 inches thick)
A--6 to 11 inches; dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; weak moderate subangular blocky structure; hard, friable, sticky; common roots; noncalcareous; mildly alkaline; clear wavy boundary. (4 to 12 inches thick)
Bt1--11 to 16 inches; very dark gray (10YR 3/1) clay loam, black (10YR 2/1) moist; moderate medium and fine angular blocky structure; hard, firm, sticky; few clay films; common roots; noncalcareous; mildly alkaline; diffuse wavy boundary. (0 to 15 inches thick)
Bt2--16 to 38 inches; very dark gray (10YR 3/1) clay, black (10YR 2/1) moist; moderate medium and fine angular blocky structure; very hard, very firm; common clay films; evident pressure faces; few roots; 1 percent of fine calcium carbonate concretions in lower part of horizon; matrix noncalcareous; mildly alkaline; gradual wavy boundary. (8 to 24 inches thick)
Btk1--38 to 48 inches; dark gray (10YR 4/1) clay, very dark gray (10YR 3/1) moist; common coarse distinct grayish brown (10YR 5/2) and yellowish brown (10YR 5/4) mottles; moderate medium and fine angular blocky structure; very hard, very firm, sticky; common clay films; evident pressure faces; 6 percent fine calcium carbonate concretions; calcareous; moderately alkaline; clear wavy boundary. (8 to 14 inches thick)
Btk2--48 to 62 inches; yellowish brown (10YR 5/4) clay, dark yellowish brown (10YR 4/4) moist; with streaks and pockets of very dark gray (10YR 3/1); weak medium and fine angular blocky structure; extremely hard, very firm, sticky; few clay films; few pressure faces; 3 percent calcium carbonate concretions; calcareous; moderately alkaline; gradual wavy boundary. (8 to 16 inches thick)
By1--62 to 72 inches; yellow (10YR 7/6) clay, brownish yellow (10YR 6/6) moist; weak medium blocky structure; very hard, very firm, sticky; contains an estimated 10 percent gray (10YR 5/1) clayey marine shale fragments having a few faint yellowish brown (10YR 5/6) mottles and few fine prominent mottles of yellowish red (5YR 5/6); an estimated 4 percent selenite gypsum crystals; calcareous; moderately alkaline; gradual wavy boundary. (8 to 14 inches thick)
By2--72 to 90 inches; brownish yellow (10YR 6/6) clay, brownish yellow (10YR 6/6) moist; moderate fine blocky structure; very hard, very firm; contains an estimated 30 percent of light olive gray (5Y 6/2) clayey marine shale fragments; an estimated 15 percent crystals of selenite gypsum; calcareous; moderately alkaline; diffuse wavy boundary. (0 to 24 inches thick)
Cy--90 to 96 inches; olive yellow (2.5Y 6/6) clayey marine shale with clay texture that is massive and has a few prominent mottles of brownish yellow (10YR 6/6), extremely hard, extremely firm; contains an estimated 15 percent of selenite gypsum crystals; calcareous; moderately alkaline.
TYPE LOCATION: Wilson County, Texas; in micro-depression 0.25 mile north on Texas Highway 181 from Poth to Farm Road 427; then 3 miles east on Farm Road 427 to county road; then 0.6 mile north and 0.12 mile into cultivated field.
RANGE IN CHARACTERISTICS: Solum thickness is 60 to 100 inches. When dry, the soil has cracks up to 2 inches wide at the surface and extending to depths of more than 50 inches. Thickness of the mollic epipedon ranges from 20 to 55 inches and the amplitude of waviness of the lower boundary is about 15 to 30 inches. Depth to secondary carbonates ranges from 16 to 54 inches. The soil is noncalcareous in the upper part.
The A and BA horizons have hue of 10YR or 2.5Y, value of 2 to 4, and chroma of 1 or 2. Textures are loam, sandy clay loam or clay loam. The A horizons and upper Bt horizons are neutral to moderately alkaline.
The Bt1 and Bt2 horizons have hue of 10YR or 2.5Y, value of 2 to 4, and chroma of 1 or 2. Texture is clay loam or clay. Clay content of the upper 20 inches of the Bt horizon is 35 to 50 percent.
The Btk horizon has hue of 10YR, 5Y, or 2.5Y, value of 4 to 6, and chroma of 1 to 6. Redoximorphic features are in shades of brown, yellow, gray or red. Texture is clay loam, or clay. Clay content is 35 to 55 percent. Reaction is neutral to moderately alkaline. Visible calcium carbonate in the form of films and threads, masses, or cemented nodular concretions ranges from 2 to 10 percent by volume.
The By1 and By2 have hue of 10YR, 5Y, 2.5Y, value of 5 to 7 and chroma of 3 to 8. Redoximorphic featuress are in shades of brown, yellow, gray or red. Texutre is clay loam, sandy clay loam or clay. Clay content is 30 to 50 percent. Reaction is neutral to moderately alkaline. About 0 to 15 percent by volume selenite crystals may occur. They are slightly saline to strongly saline.
The C horizon is in shades of gray, pink, brown, and yellow. It is clayey marine shale or interbedded loamy material and shale containing 0 to 25 percent selenite crystals and other salts.
COMPETING SERIES: These include the Coy series in the same family and the similar Clareville, Durant, Laparita, Lofton, and Marcelinas series. Coy soils are calcareous throughout and the amplitude of waviness of the boundary between the A and B horizons is 10 to 20 inches. Clareville soils have mollic epipedons more than 20 inches thick. Durant and Lofton soils have average soil temperatures of less than 72 degrees F. Laparita and Marcelinas soils have mixed mineralogy. In addition, Laparita soils are saline and Marcelinas soils have redder hues.
GEOGRAPHIC SETTING: Elmendorf soils occur on nearly level to gently sloping upland plains. These soils occupy the microlows in complex soils areas. In areas where slopes are greater than 1 percent, these soils occur as valleys in a complex surface of valleys and swells that are perpendicular to the slope contours. Slope gradients are dominantly near 2 percent, but range from 0 to 5 percent. The soil formed in calcareous clayey marine shales. The mean annual precipitation ranges from 28 to 36 inches and mean annual temperature ranges from 70 to 73 degrees F. Frost free days range from 270 to 290 days and elevation ranges from 150 to 750 feet. Annual Thornthwaite P-E indices range from 40 to 50.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Clareville, Coy, Laparita, and Marcelinas series and the Denhawken and Monteola series. Clareville and Laparita soils occur at lower elevations. Coy, Denhawken, Marcelinas, and Monteola soils occur on similar surfaces. Denhawken soils lack mollic epipedons and usually occur on micro ridges or knolls in a complex with Elmendorf soils. Monteola soils are clayey throughout and have intersecting slickensides.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is slow on 0 to 1 percent slopes; medium on 1 to 3 percent slopes and high on 3 to 5 percent slopes. Internal drainage is slow. Permeability is very slow.
USE AND VEGETATION: Mostly cultivated. Main crops are grain sorghum, cotton, corn, and small grains. Pastures are mostly improved bermudagrass. Native vegetation is mainly mesquite, cacti, live oak, little bluestem, tricloris, sideoats grama, lovegrass, Arizona cottontop, and vine-mesquite.
DISTRIBUTION AND EXTENT: Northern Rio Grande Plain , Blackland Prairie and Claypan Major Land Resource Areas of Texas. This series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Wilson County, Texas; 1972.
REMARKS: This series was formerly included with Clareville, Heiden, and Burleson soils.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 48 inches. (Ap, A, Bt1, Bt2 and Btk1 horizons)
Argillic horizon - 16 to 48 inches. (Bt2, Btk1 and Btk2 horizons)
Vertic feature - pressure faces below a depth of 16 inches and cracks to the surface when dry..