LOCATION BERNARD TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Vertic Argiaquolls
TYPICAL PEDON: Bernard clay loam--cropland. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 6 inches; very dark gray (10YR 3/1) clay loam, dark gray (10YR 4/1) dry; moderate medium granular structure; very hard, friable; few iron manganese concretions; slightly acid; clear smooth boundary. (3 to 8 inches thick)
Btg1--6 to 22 inches; very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry; moderate medium subangular blocky and granular structure; very hard, firm; common fine and very fine pores; patchy clay films on faces of peds; few iron manganese concretions; slightly acid; gradual wavy boundary. (5 to 20 inches thick)
Btg2--22 to 35 inches; very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry; weak and moderate medium and coarse angular blocky structure; extremely hard, very firm; few grooved and polished pressure faces 2 to 5 inches across; few very fine pores; thin clay films on faces or peds; Ap and B1 material in crack fillings; few iron manganese concretions; neutral; diffuse wavy boundary. (8 to 25 inches thick)
Btg3--35 to 50 inches; dark gray (N 4/0) clay, gray (N 5/0) dry, few fine distinct yellowish brown and strong brown mottles; weak coarse angular blocky structure; extremely hard, very firm; few grooved and polished pressure faces 2 to 5 inches across; few patchy clay films on faces of peds; few iron manganese concretions; mildly alkaline; gradual wavy boundary. (10 to 30 inches thick)
Btg4--50 to 60 inches; grayish brown (2.5Y 5/2) clay, light brownish gray (2.5Y 6/2) dry; common medium faint to distinct yellowish brown mottles; weak subangular structure; extremely hard, very firm; few iron manganese concretions; few fine pitted calcium carbonate concretions; noncalcareous in matrix; moderately alkaline; gradual wavy boundary. (8 to 30 inches thick)
BC--60 to 78 inches; brown (10YR 5/3) clay loam, pale brown (10YR 6/3) dry; common coarse distinct strong brown (7.5YR 5/6) and grayish brown (2.5Y 5/2) mottles; very hard, firm; few fine and medium calcium carbonate concretions; noncalcareous in matrix; moderately alkaline; gradual smooth boundary. (0 to 30 inches thick)
2C--78 to 90 inches; strong brown (7.5YR 5/6), sandy clay loam, reddish yellow (7.5YR 6/6), dry; massive; hard, fr1able; calcareous; moderately alkaline.
TYPE LOCATION: Fort Bend County, Texas; about 0.3 mile east of Tavener which is about 10 miles west of Rosenberg, 450 feet east and 300 feet south of intersection of an unpaved road and U.S. Highway 90 A.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to more than 80 inches. The mollic epipedon ranges from 16 to 50 inches thick and includes the upper part of the argillic horizon in most pedons.
The A horizon has hue of 10YR, 2.5Y, or N, value of 2 or 3, and chroma of 2 or less. Texture is mostly clay loam, but ranges to loam. Reaction is medium acid or neutral.
The Btg1 horizon has hue of 10YR, 2.5Y, 5Y, or N, values of 2 or 3, and chroma of 1 or less. It is clay loam or clay and contains more than 35 percent clay. Reaction is medium acid or neutral.
The lower Btg horizons have hue of 10R, 2.5Y, 5Y, or N, value of 2 to 5, and chroma of 2 or less. Mottles of yellow or brown range from none to common. It is clay, clay loam, or silty clay containing 35 to 60 percent clay. Reaction is slightly acid to moderately alkaline. A few concretions of calcium carbonate are below depths of 36 inches in most pedons.
The BC or BCk horizon, where present, is gray, grayish brown, or brown, or it is mottled olive, yellow, and brown. Reaction is neutral through moderately alkaline and in some pedons the soil is calcareous. Depth to the redder, sandier 2C horizon ranges from 60 to more than 80 inches; and it is absent in some pedons.
COMPETING SERIES: These are the Fiat and Mayes series in the same family and the Bonham, Edna, Jeanerette, Lake Charles, Mabank, Morey, Muldrow, and Wilson series. Fiat soils have a 20 to 40 inch sola over limestone. Mayes soils have A horizons thicker than 8 inches and are of cooler soil temperatures. Bonham soils are not dominated by gray colors in the Bt horizon and have mixed mineralogy. Edna, Mabank, and Wilson soils have ochric epipedons. Jeanerette and Morey soils are of a fine-silty textural family. Lake Charles soils lack Bt horizons and have intersecting slickensides. Muldrow soils have mixed mineralogy and lack vertic properties.
GEOGRAPHIC SETTING: Bernard soils occur on nearly level coastal prairies. Slopes are mainly less than 1 percent but areas bordering narrow natural drains range to 5 percent. Bernard soils formed in fine textured, unconsolidated sediments of Pleistocene age (Beaumont formation). The mean annual temperature in the area of the soils distribution is about 68 to 70 degrees F.; mean annual precipitation, which is about evenly distributed throughout the year, is 40 to 50 inches, and Thornthwaite annual P-E indices are 54 to 75.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Edna and Lake Charles series and the Addicks, Clodine, Katy; and Midland series. Addicks and Clodine soils have coarse-loamy control sections. Katy soils have thick light colored loamy A horizons and mottled red, yellow, and gray Bt horizons. Midland soils lack mollic epipedons and are poorly drained.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; very slow runoff; very slow to slow internal drainage; very slow permeability. The soil is saturated within 2 feet of the surface during the winter and early spring.
USE AND VEGETATION: Mainly used for growing corn, cotton, grain sorghums, and rice. A few areas are in improved pastures of bermudagrass, bahiagrass, and dallisgrass. Native vegetation is tall prairie grasses, mainly andropogons and paspalums, and a few widely spaced elm and huisache trees.
DISTRIBUTION AND EXTENT: Coastal Prairie of Texas and Louisiana. The series is extensive, the estimated area is about 500,000 acres.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Fort Bend County, Texas; 1952.
REMARKS: Diagnostic horizons recognized in this pedon are:
Mollic epipedon - 0 to 35 inches
Argillic horizon - 6 to 50 inches, high shrink-swell, low chroma colors due to wetness
ADDITIONAL DATA: S55TX-79-91, Published in SSIR-30 and in Ft. Bend County Soil Survey Report.