Established Series


The Wiergate series consists of very deep, well drained, very slowly permeable soils that formed in weakly consolidated calcareous clays and marls. These soils are on nearly level to gently sloping uplands in the coastal plains. The slope is dominantly less than 5 percent but ranges to 12 percent.

TAXONOMIC CLASS: Very-fine, smectitic, thermic Typic Hapluderts

TYPICAL PEDON: Wiergate clay, on a smooth concave slope of 4 percent, midway between micro-high and micro-low, in forest.
(Colors are for moist soil unless otherwise specified.)

A--0 to 21 inches; black (10YR 2/1) clay; strong medium angular blocky and strong medium subangular blocky structure; extremely hard, very firm; common fine and medium roots; few coarse roots; few fine pores; slightly acid; clear wavy boundary. (2 to 36 inches thick)

Bss1--21 to 27 inches; pale olive (5Y 6/3) clay; many fine faint gray (5Y 6/1) mottles; strong medium angular blocky structure; extremely hard, very firm; few medium and coarse roots; few slickensides; few pitted concretions of calcium carbonate; calcareous; moderately alkaline; clear wavy boundary. (2 to 25 inches thick)

Bss2--27 to 50 inches; gray (5Y 6/1) clay; many fine and few medium distinct olive yellow (5Y 6/6) and few medium prominent greenish gray (5G 6/1) mottles; moderate medium angular blocky structure; extremely hard, very firm; many large intersecting slickensides. Few concretions of calcium carbonate; calcareous; moderately alkaline; diffuse wavy boundary. (10 to 30 inches thick)

Bkss--50 to 75 inches; mottled gray (5Y 6/1), light yellowish brown (2.5Y 6/4) and brownish yellow (10YR 6/6) clay; moderate medium angular blocky structure; extremely hard, very firm; many large intersecting slickensides; few pitted concretions of calcium carbonate; few soft masses of calcium carbonate; calcareous; moderately alkaline.

TYPE LOCATION: Jasper County, Texas; from the intersection of U. S. Highway 190 and U. S. Highway 96 in Jasper; go 1.6 miles south on U. S. Highway 96, 0.4 mile east on private road, 900 feet southwest on forest trail, 50 feet south in forest.

RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to 80 inches. The weighted average clay content of the particle-size control section ranges from 60 to 70 percent. When dry, cracks 1/2 to more than 1 inch wide extend from the surface to a depth of more than 12 inches. Cracks remain open from 60 to 90 cumulative days in most years. Slickensides and wedge-shaped peds begin at a depth of 10 to 24 inches. Undisturbed areas have gilgai microrelief with microknolls about 4 to 12 inches above the microdepressions. Distance from the center of the microknoll to the center of the microdepression ranges from 4 to about 15 feet. Colors with chroma of 2 or less in the subsoil are considered to be litho-chromic. Mottles with chroma of 3 or more, or redox concentrations, are considered to be relic or litho-chromic.

The A horizon ranges from 2 inches thick on the micro-high to 36 inches thick in the micro-low and is about 20 inches in most of the pedons. The A horizon has colors of dark gray or black hue of 10YR and 2.5Y, value of 2 or 3, and chroma of 1 or less. Reaction ranges from slightly acid through mildly alkaline. Calcium carbonate concretions range from none to few.

The Bss and Bkss horizons have colors of gray, olive, brown or yellow hue of 10YR, 2.5Y, and 5Y, value of 3 to 7, and chroma of 1 to 6. Matrix is calcareous. Concretions of calcium carbonate range from few to common, being mostly pitted in the upper part; few soft masses of calcium carbonate range from none to few in the lower Bw horizons. Mottles are in shades of yellow, brown, gray, and olive and range from few to many. Slickensides range from common to many and are a few inches to a few feet across.

COMPETING SERIES: These are the Billyhaw, Pledger, and Trinity series in the same family, and the Burkeville, LaCerda and Redco series. Burkeville, LaCerda, and Redco soils have higher values and higher chroma within 12 inches of the surface; in addition, LaCerda and Redco soils have sola that are noncalcareous in the matrix. Billyhaw soils are poorly drained, deep and have brighter colors. Pledger and Trinity soils are on flood plains.

GEOGRAPHIC SETTING: Wiergate soils are on broad, nearly level to gently sloping uplands. Slopes are usually plane or slightly concave. Slopes are mainly less than 5 percent but range to 12 percent. These soils formed from weakly consolidated clays and marls of Tertiary age, mainly of the Fleming formation. Mean annual rainfall ranges from 48 to 55 inches; Mean annual temperature ranges from 66 to 70 degrees F., and the Thornthwaite annual P-E indices exceed 64.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Burkeville, Garner, and Redco series, and the Etoile and Woodville series. Burkeville and Redco soils are on similar positions. Etoile and Woodville soils are mostly slightly higher in the landscape and have argillic horizons. Garner soils are on ancient stream terraces.

DRAINAGE AND PERMEABILITY: Wiergate soils are somewhat poorly drained. The upper horizons are saturated for a few months in the cool season. Runoff is slow to medium and permeability is very slow.

USE AND VEGETATION: Most areas are used for forest. The main trees are shortleaf and loblolly pines, red oak, white oak, and sweetgum. Some areas have been cleared and are used for pasture.

DISTRIBUTION AND EXTENT: Eastern Texas and Louisiana in MLRA 133B. The series is of moderate extent.


SERIES ESTABLISHED: Jasper County, Texas; 1980.

REMARKS: These soils were formerly mapped with the Houston series. They were classified as Typic Pelluderts 1/94.

Diagnostic Horizons:

Mollic epipedon - 0 to 21 inches.

Cambic horizon - 21 to 75 inches.

National Cooperative Soil Survey