LOCATION BRAZORIA                TX

Established Series
Rev. GWC-RM
09/2015

BRAZORIA SERIES

The Brazoria series consists of very deep, moderately well drained, very slowly permeable soils formed in clayey alluvial sediments on the flood plains of the Brazos and Colorado Rivers. These gently to moderate sloping soils occur on flood plains of the Coastal Plains. Slope ranges from 0 to 5 percent. Mean annual precipitation range from 1092 to 1397 mm (43 to 55 in), and mean annual air temperature is about 19.5 to 21.7 degrees C (67 to 71 degrees F).

TAXONOMIC CLASS: Very-fine, smectitic, hyperthermic Chromic Hapluderts

TYPICAL PEDON: Brazoria clay, on a nearly level 0.2 percent slope, in woodland; elevation is 18 m (59 ft) (Colors are for moist soil unless otherwise stated.)

A--0 to 14 cm (0 to 6 in); dark brown (7.5YR 3/2) clay; moderate medium wedge structure parts to moderate medium angular blocky; firm; many very fine roots and common fine roots; common very fine pores; 20 percent pressure faces on all faces of peds; 1 percent fine carbonate nodules; slight effervescence; slightly alkaline; gradual smooth boundary. (Thickness is 13 to 18 cm [5 to 7 in].)

Bss1--14 to 42 cm (6 to 17 in); dark brown (7.5YR 3/2) clay; moderate medium wedge structure parts to moderate medium angular blocky; firm; common very fine roots; common very fine pores; 5 percent slickensides (pedogenic); 1 percent fine carbonate nodules; slight effervescence; moderately alkaline; gradual wavy boundary. (Combined thickness of the Bss horizons is 98 to 155 cm [39 to 61 in])

Bss2--42 to 70 cm (17 to 28 in); brown (7.5YR 4/2) clay; moderate medium wedge structure parts to moderate medium angular blocky; firm; common very fine roots; common very fine pores; 15 percent slickensides (pedogenic); 1 percent fine distinct dark reddish brown (5YR 3/4), moist, masses of oxidized iron with diffuse boundaries on slickensides; slight effervescence; moderately alkaline; clear wavy boundary.

Bss3--70 to 90 cm (28 to 36 in); 90 percent reddish brown (5YR 4/4) and 10 percent dark reddish brown (5YR 3/2) clay; moderate medium wedge structure parts to moderate medium angular blocky; firm; common very fine roots; common very fine pores; 10 percent slickensides (pedogenic); 3 percent fine black (10YR 2/1), moist, iron-manganese nodules with sharp boundaries in matrix; 1 percent fine faint reddish brown (5YR 5/4), moist, carbonate nodules; strong effervescence; moderately alkaline clear wavy boundary.

Bssb1--90 to 125 cm (36 to 49 in); very dark brown (10YR 2/2) clay; strong medium wedge structure parts to strong medium angular blocky; firm; common very fine roots; common very fine pores; 30 percent slickensides (pedogenic); 2 percent fine prominent reddish brown (5YR 4/4), moist, masses of oxidized iron with diffuse boundaries on slickensides; 1 percent fine carbonate masses; slight effervescence; moderately alkaline clear smooth boundary.

Bssb2--125 to 146 cm (49 to 58 in); 90 percent very dark brown (7.5YR 2.5/2) and 10 percent black (7.5YR 2.5/1) clay; strong coarse wedge structure parts to strong coarse angular blocky; firm; common very fine roots; common very fine pores; 35 percent slickensides (pedogenic); 1 percent fine 10YR 2/1), moist, iron-manganese nodules with sharp boundaries in matrix and 2 percent fine 5YR 4/4), moist, masses of oxidized iron with clear boundaries on slickensides; 4 percent fine distinct reddish yellow (7.5YR 6/6), moist, carbonate nodules and 2 percent fine carbonate masses; slight effervescence; moderately alkaline gradual smooth boundary. (Combined thickness of Bssb horizons is 98 to 155 cm [39 to 61 in].)

Bkssb1--146 to 170 cm (58 to 67 in); 90 percent dark brown (7.5YR 3/3) and 10 percent dark brown (7.5YR 3/2) clay; moderate coarse wedge structure parts to moderate medium angular blocky; very firm; common very fine roots; common very fine pores; 30 percent slickensides (pedogenic); 1 percent medium prominent reddish brown (2.5YR 4/4), moist, masses of oxidized iron with sharp boundaries in matrix and 1 percent fine black (10YR 2/1), moist, iron-manganese nodules with sharp boundaries in matrix; 3 percent fine carbonate nodules; strong effervescence; moderately alkaline gradual smooth boundary.

Bkssb2--170 to 203 cm (67 to 80 in); 30 percent dark reddish brown (5YR 3/2) and 70 percent dark reddish brown (5YR 3/3) clay; moderate coarse wedge structure parts to moderate medium angular blocky; very firm; common very fine roots; common very fine pores; 25 percent slickensides (pedogenic); 1 percent fine prominent red (2.5YR 4/6), moist, masses of oxidized iron with diffuse boundaries in matrix and 1 percent fine black (10YR 2/1), moist, manganese masses with sharp boundaries in matrix and 2 percent fine distinct reddish brown(5YR 4/3), moist, iron depletions with clear boundaries on slickensides and 2 percent fine black (10YR 2/1), moist, iron-manganese nodules; 1 percent fine pink (7.5YR 7/3), moist, carbonate nodules; strong effervescence; slightly alkaline. (Combined thickness of Bkss horizons is 35 to 57 cm [14 to 22 in].)

TYPE LOCATION: Fort Bend County, Texas; from the intersection of US Highway 59 and FM Road 762, 2.8 miles east on FM 762 to junction with FM 2759; 4.8 miles southeast on FM 2759 to junction with County Road Jones River; 0.7 mile south in rangeland. USGS topographic quadrangle: Sugar Land; Latitude: 29 degrees, 30 minutes, 32 seconds N; Longitude: 95 degrees, 37 minutes, 47.60 seconds W; Datum: WGS84. UTM Easting 245083 m, UTM Northing 3267251 m, UTM Zone 15.

RANGE IN CHARACTERISTICS:
Soil Moisture: Udic soil moisture regime. The soil moisture control section is not dry in any part for as long as 90 days in normal years.
Mean annual soil temperature: 21.7 to 22.2 degrees C (71 to 72 degrees F)

Vertic features: 13 to 203 cm (5 to 80 in)

Particle-size control section (weighted average)
Clay content: 60.0 to 72 percent

A Horizon:
Hue: 5YR or 7.5YR
Value: 2 or 3
Chroma: 3 or 4
Texture: clay or silty clay
Clay content: 50 to 75 percent
Sand content: 0.8 to 5 percent
Redox concentrations: 0 or 1 percent, shades of red or brown
Identifiable secondary carbonate: amount-0 to 2 percent, kind-concretions
Calcium carbonate equivalent: 0 to 18 percent
Effervescence: none to strong
Reaction: slightly alkaline or moderately alkaline

Bss Horizons:
Hue: 2.5YR to 7.5YR
Value: 3 to 5
Chroma: 2 to 6
Texture: clay
Clay content: 55 to 75 percent
Sand content: 0.5 to 7.5 percent
Redox concentrations: 0 to 2 percent, shades of yellow, brown, or red
Redox depletions: 0 to 1 percent, shades of gray
Iron-manganese concentrations: amount-0 to 1 percent; kind-nodules
Identifiable secondary carbonate: amount-0 to 2 percent, kind-concretions
Calcium carbonate equivalent: 0 to 17 percent
Effervescence: none to strong
Reaction: slightly alkaline or moderately alkaline

Bkss Horizon (where present):
Hue: 2.5YR to 7.5YR
Value: 3 to 5
Chroma: 2 to 6
Texture: clay
Clay content: 55 to 75 percent
Sand content: 0.5 to 7.5 percent
Redox concentrations: 0 to 2 percent, shades of yellow, brown, or red
Redox depletions: 0 to 1 percent, shades of gray
Iron-manganese concentrations: amount-0 to 1 percent; kind-nodules
Identifiable secondary carbonate: amount-0 to 2 percent, kind-concretions
Calcium carbonate equivalent: 0 to 17 percent
Effervescence: none to strong
Reaction: slightly alkaline or moderately alkaline

Bssb Horizons (Where present):
Hue: 2.5YR to 7.5YR
Value: 2 to 5
Chroma: 2 to 6
Texture: clay
Clay content: 55 to 75 percent
Sand content: 0.5 to 7.5 percent
Redox concentrations: 0 to 5 percent, shades of yellow, brown, or red
Redox depletions: 0 to 1 percent, shades of gray
Iron-manganese concentrations: amount-0 to 1 percent; kind-nodules
Identifiable secondary carbonate: amount-0 to 2 percent, kind-concretions
Calcium carbonate equivalent: 0 to 17 percent
Effervescence: none to strong
Reaction: slightly alkaline or moderately alkaline

Bkssb Horizons:
Hue: 2.5YR to 7.5YR
Value: 3 to 5
Chroma: 2 to 6
Texture: clay
Clay content: 60 to 75 percent
Sand content: 0.5 to 7.5 percent
Redox concentrations: 0 to 8 percent, shades of yellow, brown, or red
Redox depletions: 0 to 5 percent, shades of gray or brown
Iron-manganese concentrations: few; nodules
Identifiable secondary carbonate: few
Calcium carbonate equivalent: 0 to 17 percent
Effervescence: strongly
Reaction: slightly alkaline or moderately alkaline

COMPETING SERIES: This is the Dylan series in the same family. Similar soils are Morse, Pledger and Ships series.
Dylan soils: have iron depletions due to current day wetness within 102 cm (40 in) of the surface.
Morse soils: a fine particle-size control section; thermic temperature regime.
Pledger soils: chroma of 1 or 2 and value of 3 or less in the upper 30 cm (12 in).
Ships soils: thermic temperature regime.

GEOGRAPHIC SETTING:
Parent material: clayey alluvium
Landscape: River valleys on flat Coastal Plains
Landform: Flood plains
Slope: 0 to 5 percent, but mostly less than 1 percent
Mean annual precipitation: 1092 to 1397 mm (43 to 55 in)
Thornthwaite P-E Index: 60 to 66
Mean annual air temperature: 19.5 to 21.7 degrees C (67 to 71 degrees F)
Frost-free period: 271 to 365 days
Elevation: 1.5 to 52 m (5 to 170 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Pledger series and the Asa, Clemville, Lake Charles, Laewest, and Norwood series.
Pledger soils: on a similar landform; have darker colors to greater depth.
Asa and Norwood soils: on a slightly higher landform; loamy throughout
Clemville soils: on a slightly higher landform; have a fine-silty particle-size control sections.
Lake Charles and Laewest soils: are on slightly higher landform that does not have a chance for flooding; have darker colors to a greater depth

DRAINAGE AND PERMEABILITY: Moderately well drained. Permeability is very slow. Runoff is high on slope less than 1 percent; very high on slope greater than 1 percent. The overwash phase is somewhat poorly drained. The soil floods rarely or commonly, except where protected

USE AND VEGETATION: Mainly used as cropland for production of cotton, sorghum, corn, and soybeans. Some areas are used for improved pasture of bermudagrass, dallisgrass, and white clover. Native vegetation is pecan, elm, hackberry, oak, and ash trees and mid and tall grasses.

DISTRIBUTION AND EXTENT: Mainly along the lower reaches of the Brazos and Colorado Rivers; Land Resource Region-T; MLRA-150A. The series is of large extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Brazoria County, Texas; 1978.

REMARKS: Classification change from mixed to smectitic based laboratory data from Colorado County. Laboratory data from Brazoria County indicates mixed mineralogy, but very close to smectitic. Type location changed during Soil Data Join Recorrelation (2014) to a location with characterization data.

Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 25 to 100 cm (10 to 40 in) (Bss horizon(s))
Ochric epipedon: 0 to 14 cm (0 to 6 in). (A horizon)
Cambic horizon: 14 to 203 cm (6 to 203 in). (Bss1, Bss2, Bss3, Bssb1, Bssb2, Bsskb1 and Bsskb2 horizons)
Secondary carbonates: 14 to 203 cm (6 to 80 in) (Bss1, Bss2, Bss3, Bssb1, Bssb2, Bsskb1 and Bsskb2 horizons)
Vertic features (slickensides): 14 to 203 cm (5 to 80 in). (Bss1, Bss2, Bss3, Bssb1, Bssb2, Bsskb1 and Bsskb2 horizons)

ADDITIONAL DATA: National Soil Survey Laboratory samples S76TX-039-5; S76TX-477-1; S10TX1573010; S10TX1573011; S10TX6002761. The S10TX6002761 pedon was part of the Rapid Carbon Assessment initiative.

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014

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National Cooperative Soil Survey
U.S.A.