LOCATION SURFSIDE                TX

Established Series
JDC-GWC-RM
02/2026

SURFSIDE SERIES

Depth class: Very deep
Drainage class: Very poorly drained
Flooding frequency and duration: Occasional, brief
Saturated hydraulic conductivity: Low to moderately low
Parent material: Clayey alluvium
Slope: 0 to 1 percent
Mean annual air temperature: 22 degrees C (72 degrees F)
Mean annual precipitation: 1270 millimeters (50 inches)

TAXONOMIC CLASS: Very-fine, smectitic, hyperthermic Vertic Endoaquolls

TYPICAL PEDON: Surfside clay on a nearly level flood plain at an elevation of 1.5 meters. (Colors are for moist soil unless otherwise stated.)

Ag1--0 to 36 centimeters; 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; few fine interstitial pores; 25 percent fine prominent strong brown (7.5YR 4/6) masses of oxidized iron; moderately saline; slightly alkaline (pH 7.8); gradual smooth boundary.

Ag2--36 to 81 centimeters; dark gray (10YR 4/1) clay, gray (10YR 5/1) dry; moderate coarse prismatic structure parting to moderate medium and fine angular blocky structure; very firm; few fine roots; 1 percent fine distinct yellowish brown (10YR 5/4) masses of oxidized iron; 1 percent fine faint gray (10YR 6/1) iron depletions; 1 percent thin light gray (10YR 7/1) silt material coating prism faces; strongly saline; slightly alkaline (pH 7.8); clear smooth boundary. (Ag horizons are 40 to 102 centimeters thick)

Bkg--81 to 200 centimeters; dark reddish brown (5YR 3/3) clay, reddish brown (5YR 4/3) dry; weak medium angular blocky structure; very firm; few fine roots; 8 percent fine and medium distinct gray (7.5YR 6/1) and 1 percent fine distinct very dark gray (10YR 3/1) iron depletions; 3 percent carbonate concretions; strongly effervescent (HCl); strongly saline; moderately alkaline (pH 8.4).

TYPE LOCATION: Brazoria County, Texas; Approximately 2.7 kilometers (1.7 miles) south of the Oyster Creek community and very close to Horseshoe Lake, 0.42 kilometers (0.26 miles) east-southeast of the intersections of FM 332 and Baldwin Road (FM 523) and 0.55 kilometers (0.34 miles) from the intersection of FM332 and East Union Bayou Road, and 15 meters (50 feet) south of FM 332; USGS quadrangle: Freeport, Texas

Latitude: 28.9799977
Longitude: -95.3337455
Datum: WGS84
Coordinate Source: Estimated from other source

RANGE IN CHARACTERISTICS:
Depth to bedrock: Greater than 200 centimeters
Moisture regime: Aquic
Particle-size control section (weighted average): 25 to 100 centimeters
Sand content--1 to 9 percent
Clay content--64 to 78 percent

Ag horizons:
Hue--7.5YR or 10YR
Value--2 to 5
Chroma--1 or 2
Texture--silty clay or clay
Redox concentrations--15 to 30 percent shades of brown or yellow
Iron depletions--0 to 30 percent shades of gray
Secondary carbonates--0 to 15 percent concretions or masses
Reaction--neutral to moderately alkaline (pH 7.0 to .8.4)

Bkg horizon:
Hue--2.5YR to 7.5YR
Value--3 to 5
Chroma--2 to 6
Texture--clay
Redox concentrations--15 to 30 percent shades of brown or yellow
Iron depletions--5 to 30 percent shades of gray
Secondary carbonates--0 to 15 percent concretions or masses
Effervescence (HCl)--none to strong
Reaction--slightly to moderately alkaline (pH 7.4 to 8.4)

Some pedons have C or 2C horizons below 152 cm (60 in) 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 clayey or sandy layers.

COMPETING SERIES: There are no other series in the same family. Nearby soils within the same subgroup include the Zummo series.
Zummo soils: are in the fine family.

GEOGRAPHIC SETTING:
Parent material: Clayey alluvium
Landscape: Coastal Plains
Landform: Flood plains
Slope: 0 to 1 percent
Mean annual precipitation: 812 to 1194 millimeters (32 to 47 inches)
Mean annual air temperature: 21 to 22 degrees C (70 to 72 degrees F)
Frost-free period: 330 to 365 days
Elevation: 0 to 3 meters (10 feet)

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Galveston, Ijam, Mustang, Pledger, Tracosa, Velasco, and Veston series.
Galveston and Mustang soils: are sandy throughout and occur on dunes on barrier islands.
Ijam soils: are on anthropogenic dredge spoil deposits.
Pledger soils: are slightly higher on nearby landscapes, have better drainage and contain slickensides
Tracosa soils: do not have a thick dark soil surface horizon and have daily tidal influence
Velasco soils: are on flood plains and are calcareous throughout.
Veston soils: do not have a thick dark soil surface horizon, are on barrier island flats, and have coarser textures throughout.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: Very poorly drained
Saturated hydraulic conductivity: Low to moderately low
Flooding frequency and duration: Occasional, brief
Seasonal water table: 0 centimeters (at the soil surface but fluctuates throughout the year)
Surface runoff: High

USE AND VEGETATION:
Major use: Wildlife habitat
Vegetation: Gulf cordgrass, hartweg's paspalum, little bluestem, saltgrass, saltmeadow cordgrass, switchgrass
Ecological Site: R150BY551TX-Salty Prairie

DISTRIBUTION AND EXTENT:
General Area: On mainlands near bays along the central coast of Texas
Land Resource Region: T-Atlantic and Gulf Coast Lowland Forest and Crop Region
MLRA(s): 150B-Gulf Coast Saline Prairies
Extent: Moderate

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Special Projects Office

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 on 11/2000 based on typifying pedon description. These soils do not have slickensides or wedge-shaped peds, so do not classify as Vertisols.

Typical pedon taxonomic features:
Aquic conditions: 0 to 200 centimeters
Mollic epipedon: 0 to 36 centimeters
Redox concentrations: 0 to 81 centimeters
Redox depletions: 36 to 200 centimeters
Reduced matrix: 0 to 200 centimeters
Secondary carbonates: 81 to 200 centimeters
Vertic features: 1 centimeter cracks extend to 51 centimeters and COLE > 0.9
Taxonomic version: Keys to Soil Taxonomy, 13th edition (2022)

ADDITIONAL DATA: National Soil Survey Laboratory data from Brazoria County, Texas (S76TX-039-006) -(76PO756, 76PO758).

OSD User Pedon ID: 2015TX039423
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National Cooperative Soil Survey
U.S.A.