LOCATION LEEMONT TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, hyperthermic Chromic Udic Haplusterts
TYPICAL PEDON: Leemont clay - rangeland. Described near a microknoll. (Colors are for dry soil unless otherwise stated.)
A1--0 to 5 inches; gray (10YR 5/1) clay, dark gray (10YR 4/1) moist; moderate fine angular blocky structure; very hard, very firm, very sticky, very plastic; common fine roots; strongly effervescent; moderately alkaline; gradual smooth boundary. (3 to 10 inches thick)
A2--5 to 26 inches; light gray (10YR 6/1) clay, gray (10Yr 5/1) moist; weak fine and medium angular blocky structure; common wedge-shaped aggregates with the long axis tilted 30 to 45 degrees from the horizontal; extremely hard, very firm, very sticky, very plastic; common fine roots; few distinct slickensides; shiny grooved pressure faces on surfaces of peds; strongly effervescent; moderately alkaline; diffuse wavy boundary. (10 to 30 inches thick)
Bk1--26 to 50 inches; light brownish gray (10YR 6/2) clay, grayish brown (10YR 5/2) moist; weak medium angular blocky structure; common wedge-shaped aggregates tilted 30 to 45 degrees from the horizontal; extremely hard, very firm, very sticky, very plastic; common distinct slickensides; common calcium carbonate concretions; violently effervescent; moderately alkaline; gradual wavy boundary. (8 to 28 inches thick)
Bk2--50 to 60 inches; pink (7.5YR 7/4) clay, light brown (7.5YR 6/4) moist; weak coarse angular blocky structure; common wedge-shaped aggregates tilted 30 to 45 degrees from the horizontal; common distinct slickensides; shiny pressure faces on surfaces of peds; few masses of calcium carbonate; common fine calcium carbonate concretions; violently effervescent; moderately alkaline; gradual wavy boundary. (6 to 14 inches thick)
BCk--60 to 80 inches; pink (7.5YR 7/4) clay, light brown (7.5YR 6/4) moist; structureless, but has vertical and horizontal fractures of the clay especially along apparent bedding planes; very hard, firm, very sticky, very plastic; 8 percent masses of calcium carbonate; common medium prominent white (10YR 8/1) mottles; violently effervescent; moderately alkaline.
TYPE LOCATION: DeWitt County, Texas; from the intersection of U.S. Highways 87 and 183 in Cuero, Texas; 10 miles southwest and northwest on U.S. Highway 87; then 4.2 miles west on Farm Road 2542 and 200 feet north of the highway in rangeland.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 40 to 80 inches. Gilgai relief, in virgin areas, consists of a series of microhighs and microlows about 5 to 16 feet wide. Clay content ranges from 40 to 60 percent clay.
The A horizon has hue of 10YR or 2.5Y, value 4 to 6 and chroma of 1 or is neutral (N). A horizons that have moist color values of less than 3.5, are less than 12 inches thick in more than half of any pedon. Texture is clay. The A horizon is slightly alkaline or moderately alkaline.
The Bk horizons has hue of 7.5YR, 10YR, or 2.5Y, value of 5 or 6, and chroma of 1 to 4. Calcium carbonate concretions in the Bk horizon range from few to common.
The BC horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 6 or 7, and chroma of 1 to 4.
A C horizon occurs in some pedons. Where present, it consists of weathered, and interbedded claystone with clay texture. Colors of this material are similar to the BC horizon with mottles that are lithochromic.
COMPETING SERIES: There are no competing series in the same family. Similar soils include the Montell series and the similar Harlingen, Mercedes, Montell, Monteola, and Victoria series. The Harlingen soils have chroma of 2 or more. Mercedes soils have mean annual soil temperatures of more than 74 degrees F. and contain more than 15 percent exchangeable sodium within 30 inches of the surface. Monteola and Victoria soils have A horizons more than 12 inches thick with color values less than 5.5 dry and 2.5 moist. Montell soils contain more than 15 percent exchangeable sodium within 30 inches of the surface and occur in drier regions.
GEOGRAPHIC SETTING: Leemont soils occupy gently sloping to sloping uplands. Slope gradients are dominantly 3 to 8 percent. The regolith is calcareous clays. The mean annual precipitation ranges from 26 to 33 inches. The mean annual temperature ranges from 70 to 74
degrees F. and Thornthwaite annual P-E indices range from 36 to 46.
GEOGRAPHICALLY ASSOCIATED SOILS: These include
Monteola soils of the competing series as well as
Denhawken,
Elmendorf,
Sarnosa and
Shiner soils. Denhawken, Elmendorf and Sarnosa soils lack intersecting slickensides. In addition, Elmendorf soils have mollic epipedons and argillic horizons. Sarnosa soils have coarse-loamy control sections. Shiner soils have weakly
cemented sandstone within 20 inches of the surface.
DRAINAGE AND PERMEABILITY: Moderately well drained. Permeability is very slow. Runoff is high on 3 to 5 percent slopes and very high on slopes greater than 5 percent. Water enters the soil rapidly when it is dry and cracked and very slowly when it is wet.
USE AND VEGETATION: Largely native rangeland. Native grasses are mainly little bluestem, sideoats grama, buffalograss, Texas wintergrass and silver bluestem. Woody plants are mesquite, huisache, hackberry and thorny brush. Pricklypear is an invader.
DISTRIBUTION AND EXTENT: Northeastern part of the Rio Grande Plain of Texas. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: DeWitt County, Texas; 1973.
REMARKS: Classification change from Entic Pellusterts to Chromic Udic Haplusterts based on application of 2nd edition of Soil Taxonomy, 1999.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 5 inches. (A1 horizon)
Vertic feature - Gilgai micro relief; slickensides and wedge-shaped aggregates at depths of 5 to 60 inches.
Chromic feature - color value, moist, of 4 or more and color value, dry, of 6 or more within the upper 12 inches of the surface.