LOCATION TOPSEY             TX

TOPSEY SERIES

The Topsey series consists of moderately deep over densic material, well drained, moderately slowly permeable soils that formed in shaly and marly sediments. These soils are on gently sloping to moderately sloping erosional uplands. Surfaces are plane to concave, and slopes range from 1 to 8 percent.

TAXONOMIC CLASS: Fine-loamy, carbonatic, thermic Udic Calciustolls

TYPICAL PEDON: Topsey clay loam, on a concave 3 percent slope in rangeland. (Colors are for dry soil unless otherwise stated.)

A--0 to 8 inches; dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate very fine granular and subangular blocky structure; slightly hard, friable; common very fine, fine and few medium roots; common fine pores; few wormcasts; calcareous; moderately alkaline; clear smooth boundary. (7 to 12 inches thick)

Bw1--8 to 14 inches; grayish brown (2.5Y 5/2) clay loam, dark grayish brown (2.5Y 4/2) moist; moderate very fine granular and subangular blocky structure; hard, friable; common fine and few medium roots; common fine pores; dark stains on some ped surfaces; few very fine concretions and soft masses of calcium carbonate; about 2 percent fossil shells from 1/10 inch to 1 1/2 inches across; calcareous; moderately alkaline; clear smooth boundary. (5 to 16 inches thick)

Bw2--14 to 19 inches; light yellowish brown (2.5Y 6/4) gravelly loam, light olive brown (2.5Y 5/4) moist; moderate medium subangular blocky structure; hard, friable; common fine and few medium roots; common fine pores; few very fine concretions, threads, and soft masses of calcium carbonate; about 30 percent fossil shells from 1/10 inch to 1 1/2 inches across; few grayish shale fragments; calcareous; moderately alkaline; clear smooth boundary. (0 to 10 inches thick)

Bk--19 to 28 inches; light yellowish brown (2.5Y 6/4) silt loam, light olive brown (2.5Y 5/4) moist; few fine faint yellowish brown and pale yellow mottles; weak medium and coarse subangular blocky structure parting to moderate very fine subangular blocky; hard, friable; few fine roots; common fine pores; common soft fine and medium and few coarse masses of calcium carbonate; about 3 to 5 percent fossil shells from 1/10 inch to 1 1/2 inches across; few thin grayish shale fragments; calcareous; moderately alkaline; gradual smooth boundary. (6 to 12 inches thick)

2Cd--28 to 67 inches; pale yellow (2.5Y 7/4) marl with silty clay loam texture, light yellowish brown (2.5Y 6/4) moist interbedded with yellowish brown (10YR 5/8) and light gray (10YR 7/2) thin discontinuous shaly strata; massive; very hard, firm; few fine roots; few fine and medium soft masses of calcium carbonate; about 2 percent fossil shells 1/10 inch to 1 1/2 inches across; calcareous; moderately alkaline.

TYPE LOCATION: Coryell County, Texas; from the intersection of Texas Highway 36 and West Range Road about 3.0 miles southeast of Gatesville, 1.6 miles southwest on West Range Road, 1.8 miles southwest on Turnover Creek Road, and 950 feet north-northeast, in range.

RANGE IN CHARACTERISTICS: Solum thickness and depth to densic material ranges from 20 to 40 inches. Texture is clay loam, loam, silty clay loam, or silt loam. Silicate clay ranges from 20 to 35 percent. The calcium carbonate equivalent ranges from 40 to 80 percent. Particles coarser than very fine sand comprise more than 15 percent. Fossil shells, mainly oyster, from 1/10 inch to 1 1/2 inches across range from none to a few in the A horizon and from 1 to 15 percent in the control section. Some horizons 4 to 10 inches thick contain up to 35 percent by volume.

The A horizon has hue of 10YR or 2.5Y, value of 4 or 5, and chroma of 2 or 3. Moist values are 3.5 or less.

The B horizons have hue of 2.5Y, 10YR, or 7.5YR, value of 5 through 7, and chroma of 3 through 6. Few to common yellowish or brownish mottles and grayish shale fragments are in the lower part of most pedons. Secondary forms of calcium carbonate are most concentrated in the lower 6 inches to 1 foot of the B horizon.

The 2Cd horizon has hue of 2.5Y, 10YR, or 7.5YR, value of 5 through 7, and chroma of 2 through 8. Typically, there are mottles, streaks and thin discontinuous strata of these colors. It is dense marl of silty clay loam, clay loam, or silty clay texture. The clay content is about 10 to 20 percent more than in the solum. Some pedons are interbedded with strata of calcium carbonate, and shale. Massive beds of fossil shells are below a depth of 60 inches in some pedons.

COMPETING SERIES: These include Bolar, Carbengle, Rumley and Sunev series in the same family and Cranfill, Seawillow, and Venus series in similar families. Bolar soils are underlain by indurated limestone at depths of 20 to 40 inches. Carbengle soils formed in calcareous sandstone of Miocene age and are moist for longer periods with annual rainfall of 35 to 45 inches. Rumley soils have sola more than 60 inches thick. Sunev soils formed in alluvial or colluvial loamy sediments with sola 40 to 70 inches thick. Cranfill and Seawillow soils lack mollic epipedons. In addition, Cranfill soils have sola more than 40 inches thick. Venus soils have mixed mineralogy and sola more than 40 inches thick.

GEOGRAPHIC SETTING: Topsey soils have plane to concave surfaces with slopes of 1 to 8 percent. Typically slopes are 2 to 5 percent. They are on low hillsides and side slopes along small drains. These soils formed in the Walnut Geologic Formation of Lower Cretaceous age. Mean annual precipitation is 28 to 34 inches. Mean annual temperature is 64 to 68 degrees F. Thornthwaite annual P-E indices range from 44 to 56.

GEOGRAPHICALLY ASSOCIATED SOILS: These include Brackett, Cho, Nuff, Pidcoke, and Slidell series. Brackett soils are shallow over bedrock and lack mollic epipedons and are on convex ridgetops and shoulderslopes above Topsey soils. Cho soils are shallow to a petrocalcic horizon and are on slightly lower positions. Nuff soils have stony surfaces and are on slightly lower positions. Pidcoke soils are shallow to bedrock and are slightly higher on convex ridgetops. The clayey Slidell soils have montmorillonitic mineralogy and are on lower positions.

DRAINAGE AND PERMEABILITY: Well drained; medium surface runoff; moderately slow permeability.

USE AND VEGETATION: Mainly range but some areas are used for pasture. Native vegetation is a mid and tall grass prairie.

DISTRIBUTION AND EXTENT: In the Grand Prairie Land Resource Area. The series is of moderate extent.

MLRA OFFICE RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Coryell County, Texas; 1983.

REMARKS: Classification was changed 11/89 from Typic Calciustolls to Udic Calciustolls.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - 0 to 8 inches

Cambic horizon - 8 to 19 inches

Calcic horizon - 19 to 28 inches

Densic Material- 28 to 67 inches

ADDITIONAL DATA: NSSL-S80TX-099-005; Lab Nos. 81P-520-524. DHPT data is also available for this pedon.