LOCATION FREEPORT                TX

Established Series
JKW-KBH-AKS
09/2020

FREEPORT SERIES

The Freeport series consists of very deep, poorly drained, low saturated hydraulic conductivity (very slowly permeable) soils that formed in eolian deposits over loamy and clayey fluviomarine deposits. These nearly level soils occur on tidal flats on barrier islands. Slope ranges from 0 to 1 percent. Mean annual precipitation is about 1245 mm (49 in) and mean annual air temperature is about 20 degrees C (68 degrees F).

TAXONOMIC CLASS: Coarse-loamy, mixed, active, nonacid, hyperthermic Sodic Endoaquents

TYPICAL PEDON: Freeport fine sandy loam, on a vegetated tidal flat; 0.3 m elevation. (Colors are for moist soil unless otherwise stated.)

Ag--0 to 21 cm (0 to 8 in); greenish gray (10Y 5/1) fine sandy loam; massive; friable; nonsticky, nonplastic; nonfluid; common fine roots; very few very fine vesicular pores; 2 percent fine prominent yellowish brown (10YR 5/6) masses of oxidized iron; electrical conductivity of 28.0 dS/m by ec meter, saturated paste; sodium adsorption ratio of 51.3; slightly alkaline; abrupt smooth boundary. (15 to 33 cm [6 to 13 in] thick)

Cg1--21 to 35 cm (8 to 14 in); 70 percent greenish gray (10GY 6/1) and 30 percent greenish gray (10Y 5/1) fine sandy loam; massive; friable; nonsticky, nonplastic; nonfluid; few fine roots; 5 percent fine prominent yellowish brown (10YR 5/6) masses of oxidized iron; electrical conductivity of 57.0 dS/m by ec meter, saturated paste; sodium adsorption ratio of 71.6; slightly alkaline; clear smooth boundary.

Cg2--35 to 128 cm (14 to 50 in); 70 percent greenish gray (5GY 5/1) and 30 percent greenish gray (10GY 6/1) fine sandy loam; massive; friable; nonsticky, nonplastic; nonfluid; 8 percent medium prominent yellowish brown (10YR 5/6) masses of oxidized iron; electrical conductivity of 43.0 dS/m by ec meter, saturated paste; sodium adsorption ratio of 48.7; moderately alkaline; clear smooth boundary. (combined thickness of the Cg horizons is 51 to 122 cm [20 to 48 in])

2Cg1--128 to 170 cm (50 to 67 in); greenish gray (5GY 5/1) clay; massive; very firm; very sticky, very plastic; nonfluid; electrical conductivity of 56.0 dS/m by ec meter, saturated paste; sodium adsorption ratio of 79.5; moderately alkaline; gradual smooth boundary. (combined thickness of the 2Cg horizons is 71 to 132 cm [28 to 52 in])

2Cg2--170 to 203 cm (67 to 80 in); dark gray (N 4/), sandy clay loam; massive; firm; sticky, plastic; nonfluid; electrical conductivity of 57.0 dS/m by ec meter, saturated paste; sodium adsorption ratio of 78.1; slightly alkaline.

TYPE LOCATION:
Brazoria County, TX; from the intersection of Texas Highway 332 and the Bluewater Highway (County Road 257) on Follets Island, 9 miles northeast on the Bluewater Highway to dirt road on the northwest side of the road; 0.15 mile northwest on dirt road; 50 feet north on a tidal flat vegetated with saltflat grass and salicornia.

USGS topographic quadrangle: Sea Isle, TX
Latitude: 29 degrees 2 minutes 11.40 seconds North
Longitude: 95 degrees 10 minutes 40.50 seconds west
Datum: WGS84

UTM Easting: 287918 meters
UTM Northing: 3213987 meters
UTM Zone: 15

RANGE IN CHARACTERISTICS:

Soil moisture: A peraquic soil moisture regime.

Particle-size control section (weighted average):
Total clay content: 12 to 16 percent

Ag horizon:
Hue: 10YR or 2.5Y
Value: 5 to 7
Chroma: 1 or 2
Texture: fine sand, loamy fine sand, or fine sandy loam
Total clay content: 5 to 11 percent
Electrical conductivity (dS/m): 25 to 35
Reaction (pH): slightly or moderately alkaline (7.4 to 8.4)

Cg horizon:
Hue: 60 to 100 percent N, 10YR, 2.5Y, 5GY, 10GY, or 5B; 0 to 30 percent 10YR or 10GY
Value: 5 to 7
Chroma: 0 to 2
Texture: fine sand, loamy fine sand, fine sandy loam or very fine sandy loam
Total clay content: 5 to 18 percent
Redox concentrations: amount-0 to 15 percent; color-shades of brown, yellow, or red
Shell fragments: amount-0 to 2 percent; size- 2 to 75 mm
Electrical conductivity (dS/m): 30 to 60
Reaction (pH): slightly or moderately alkaline (7.4 to 8.4)

2Cg horizon:
(This horizon is absent in some pedons)
Hue: N, 10Y, 5GY, 10GY or 5B
Value: 4 to 7
Chroma: 0 or 1
Texture: sandy clay loam or clay loam, or clay
Total clay content: 30 to 60 percent
Redox concentrations: amount-0 to 15 percent; color-shades of brown, yellow, or red
Shell fragments: amount-0 to 10 percent; size- 2 to 75 mm
Electrical conductivity (dS/m): 50 to 120
Reaction (pH): slightly alkaline or moderately alkaline (7.4 - 8.4)

COMPETING SERIES:
This is the Karankawa and Ostermayer series in the same family. Similar soils are Nass, Madre, Mustang, Satatton, and Tatton series.
Karankawa soils submerged for longer periods; have mucky surface texture.
Nass soils: very poorly drained; have electrical conductivity values less than 25 dS/m throughout.
Madre, Mustang, Satatton, and Tatton soils: a sandy particle-size control section; siliceous mineralogy

GEOGRAPHIC SETTING:
Parent material: eolian sands over loamy and clayey fluviomarine deposits derived from igneous, metamorphic, and sedimentary rock
Landscape: barrier island
Landform: tidal flats
Slope: 0 to 1 percent but mostly less than 0.5 percent
Precipitation Pattern: Precipitation is generally uniform throughout the year with slight peaks in the spring and fall months
Mean annual precipitation: 1143 to 1295 mm (45 to 51 in)
Mean annual air temperature: 20.6 to 21.7 C (69 to 71 degrees F)
Frost-free period: 275 to 300 days
Elevation: 0 to 0.5 m (0 to 20 in)

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Brazosport Galveston, Karankawa, and and Ostermayerseries.
Galveston soils: are on a back-barrier flat landform
Karankawa soils: on a submerged tidal flat
Brazosport soils: are remnant back-barrier flats
Ostermayer soils: are same landform but do not have vegetation

DRAINAGE AND PERMEABILITY:
Drainage class: poor
Permeability class: very slow (low saturated hydraulic conductivity)
Runoff: high
Flooding: frequent frequency from daily tides, for very brief (4 to 48 hours) duration
Seasonal water table: Endosaturation occurs from near the surface to 2 m (0 to 8 feet throughout the year. As high tides recede, these areas remain saturated throughout.

USE AND VEGETATION:
Major uses: wildlife habitat
Native vegetation: saltflat grass and salicornia and other salt tolerant vegetation
Ecological sites assigned to phases and components of this series are listed below. Current ecological site assignments are in Web Soil Survey. Components of this series include the following ecological sites: Salt Flat (R150BY651TX)

DISTRIBUTION AND EXTENT:
General area: The upper Texas Gulf Coast mostly on Galveston and Follets Island
Land Resource Region: Atlantic and Gulf Coast Lowland Forest and Crop Region(T)
Major Land Resource Areas: 150B - Gulf Coast Saline Prairies
Extent: small

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Temple, Texas

SERIES PROPOSED: Galveston County, Texas, 2020. The name is from a municipality near the type location.

REMARKS: The series was formerly included in the Mustang series. The series was separated based on differences in water table depth and salinity.

Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: 25 to 100 cm (10 to 40 in)
Ochric epipedon: 0 to 21 cm (0 to 8 in) (Ag horizon)
Endosaturation and aquic conditions: 0 to 203 cm (0 to 80 in) (Ag, Cg1, Cg2,2Cg1 and 2Cg2 horizons)
Lithologic discontinuity: 128 to 203 cm (50 to 80 in).

Additional Comments: The lithologic discontinuity is evident as an increase in clay due to the Beaumont Formation and ancient Brazos River. This paleo-surface is deeper in pedons on Galveston Island and shallower on the southwest end of Follets Island. Some areas are firm enough during low tide to allow light vehicular traffic.

ADDITIONAL DATA: MLRA Soil Survey Office data are available on S2020TX0397032 at the series type location.

TAXONOMIC VERSION: Keys to Soil Taxonomy, Twelfth Edition, 2014.

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National Cooperative Soil Survey
U.S.A.