LOCATION SURFSIDE TXEstablished Series
TAXONOMIC CLASS: Very-fine, smectitic, hyperthermic Vertic Endoaquolls
TYPICAL PEDON: Surfside clay--on a nearly level, 0.1 percent slope, in rangeland.
(Colors are for moist soil unless otherwise stated.)
Ag1--0 to 14 inches; very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry; moderate medium subangular and angular blocky structure; very hard, very firm; many fine and medium roots; many old root cavities stained strong brown; moderately saline; slightly alkaline; gradual smooth boundary. (10 to 20 inches thick)
Ag2--14 to 32 inches; dark gray (10YR 4/1) clay, gray (10YR 5/1) dry; moderate coarse prismatic structure parting to moderate medium and fine blocky; few fine distinct yellowish brown iron concentrations, and few fine faint gray iron depletions; few prism surfaces are thinly coated with light gray silt material; very firm; few fine roots; strongly saline; slightly alkaline; clear smooth boundary. (6 to 20 inches thick)
Bg--32 to 72 inches; dark reddish brown (5YR 3/3) clay, reddish brown (5YR 4/3) dry; weak medium blocky structure; very firm; few fine roots; common fine and medium distinct gray (7.5YR 6/1), and few fine distinct very dark gray iron depletions; few calcium carbonate concretions up to 1/4 inch in diameter; strongly effervescent; strongly saline; moderately alkaline.
TYPE LOCATION: Brazoria County, Texas; 2.1 miles northeast of Freeport on Farm Road 332; southeast 0.3 mile; 300 feet south of road in rangeland.
RANGE IN CHARACTERISTICS: Solum thickness is 60 to more than 80 inches. The soil is moderately to strongly saline. Some pedons have buried horizons at depths of more than 40 inches. Some pedons have an organic surface horizon less than 2 inches thick. In most years, cracks 1 cm or more wide extend from the surface to a depth of 20 inches. Some pedons have a few slickensides.
The upper Ag horizon has hue of 10YR, value of 2 or 3, and chroma of 1 or 2. The lower Ag horizon has hues of 10YR and 7.5YR, values of 3 or 4, and chroma of 1 or 2. The A horizon is mainly clay, but includes silty clay. The organic matter content ranges from 2 to 10 percent. Reaction ranges from neutral to moderately alkaline.
The Bg horizon has hue of 2.5YR to 7.5YR, value of 3 to 5, and chroma of 2 to 6. Texture is clay. Reaction is slightly or moderately alkaline. The B horizon is commonly calcareous but some pedons are noncalcareous.
Some pedons have C or 2C horizons below 60 inches that have the same colors as the B horizons with individual strata that are reddish, brownish or yellowish. Textures range from loam to clay that is stratified with more clayey and more sandy layers.
COMPETING SERIES: There are no other series in the same family. Other similar soils are the Aransas, Harris, Iberia, Lake Charles, Lomalta, Pledger, and Velasco series. Aransas soils have fine textured control sections and are calcareous throughout. Iberia, Lake Charles, and Pledger soils are not saline. Harris soils have gray colors throughout. Lomalta soils are calcareous throughout and are in dryer climates. Velasco soils do not have gray colors in the upper part and are calcareous throughout.
GEOGRAPHIC SETTING: Surfside soils are on low terraces of the Coast Prairie. Slopes are less than 1 percent. The soils formed in calcareous clayey recent alluvium less than 10 feet above sea level. Average annual precipitation ranges from 40 to 60 inches. Mean annual air temperature is about 70 degrees to 72 degrees F. The Thornthwaite P-E indices exceed 48.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the similar Pledger and Velasco series and the Galveston, Mustang, Tracosa, and Veston series. Pledger soils are on higher and better drained positions. Velasco soils are on slightly lower and wetter positions. Galveston and Mustang soils are sandy and Veston soils are loamy. Tracosa soils have an ochric epipedon, are on lower positions, and are flooded daily by tidal action.
DRAINAGE AND PERMEABILITY: Surfside soils are poorly drained. Runoff is high, and permeability is very slow. A water table fluctuates from the soil surface to a depth of about 50 inches. The soils are occasionally flooded by fresh water during periods of high rainfall, and salt water during Gulf storms. Some low-lying areas are flooded by salt water during extremely high tides. The soil is saturated at or near the surface for periods of 4 to 6 months during the year.
USE AND VEGETATION: Used for rangeland and wildlife habitat. Native vegetation is mainly Gulf cordgrass with some other water-loving and salt tolerant grasses and sedges. When salt content is lowered, little bluestem, switchgrass, longtom, and bermudagrass are common.
DISTRIBUTION AND EXTENT: Lower Coast Prairie (MLRA 150B) and Coastal Marsh (MLRA 151) areas of Texas and possibly Louisiana. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Brazoria County, Texas; 1978.
REMARKS: Surfside soils were formerly considered a saline phase of the Pledger series.
Classification changed from Vertic Haplaquolls to Vertic Endoaquolls 11/2000 based on typifying pedon description. Some data indicate these soils may be Vertisols. Further study and characterization data of the series is needed to verify hydrology and classification.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 14 inches.
Aquic feature - dominant chroma of 2 or less with iron concentrations of higher chroma.
Vertic feature - 1 cm wide cracks extend to 20 inches in most years, have COLE of .09 or more and contain 35 percent or more clay in a layer 20 inches thick. PLE is more than 6 cm in the upper 40 inches of the soil profile.
ADDITIONAL DATA: National Soil Survey Laboratory data from Brazoria County, Texas (S76TX-039-006) -(76PO756, 76PO758).
TAXONOMIC VERSION: Soil Taxonomy, Second Edition, 1999.