LOCATION TWINPALMS TX
Established Series
DNB-JKW-KBH
02/2018
TWINPALMS SERIES
The Twinpalms series consists of very deep, somewhat poorly drained, moderately permeable soils that formed in sandy and loamy sediments dredged from submerged areas. These very gently sloping soils are on low mounds on spoil pile areas. These soils are subject to occasional flooding by high storm surge from strong tropical storms. Slope ranges from 1 to 3 percent. Mean annual precipitation is about 686 mm (27 in), and Mean annual air temperature is about 23 degrees C (73 degrees F).
TAXONOMIC CLASS: Coarse-loamy, siliceous, active, calcareous, hyperthermic Aquic Ustorthents
TYPICAL PEDON: Twinpalms fine sand--in an area of Twinpalms-Yarborough complex, 0 to 3 percent slopes on a southwest facing 2 percent slope in wildlife land at an elevation of 1.8 meters (6 ft) (Colors are for moist soil unless otherwise stated.)
A1--0 to 20 cm (0 to 8 in); light olive brown (2.5Y 5/3) fine sand, light yellowish brown (2.5Y 6/3) dry; weak fine subangular blocky structure parting to single grain; loose; 6 percent very fine and fine roots; 5 percent fine faint light yellowish brown (2.5Y 6/4) masses of oxidized iron with clear boundaries lining pores; 2 percent gravel-sized and 10 percent sand-sized seashell fragments; nonsaline; Sodium Adsorption Ratio is less than 1; very slight effervescence; slightly alkaline; clear smooth boundary.
A2--20 to 46 cm (8 to 18 in); grayish brown (2.5Y 5/2) fine sand, light brownish gray (2.5Y 6/2) dry; single grain; loose; 3 percent very fine and fine roots; 3 percent fine distinct pale yellow (2.5Y 7/4) masses of oxidized iron with sharp boundaries lining pores; 2 percent gravel-sized and 10 percent sand-sized seashell fragments; nonsaline; Sodium Adsorption Ratio is less than 1; very slightly effervescent; slightly alkaline; clear smooth boundary. (Combined thickness of the A horizons is 15 to 69 cm [6 to 27 in].)
C--46 to 76 cm (18 to 30 in); olive (5Y 5/3) fine sandy loam, pale olive (5Y 6/3) dry; massive; slightly hard, friable; 2 percent very fine and fine roots; 15 percent medium distinct greenish gray (10Y 6/1) clay balls; 2 percent fine and medium gypsum crystals; 5 percent fine and medium prominent dark yellowish brown (10YR 4/6) masses of oxidized iron with clear boundaries lining pores; 4 percent gravel-sized and 10 percent sand-sized seashell fragments; 5 percent gravel-sized serpulid reef fragments; nonsaline; Sodium Adsorption Ratio is less than 1; very slightly effervescent; slightly alkaline; clear smooth boundary. (15 to 74 cm [6 to 29 in] thick)
Cg1--76 to 102 cm (30 to 40 in); light brownish gray (2.5Y 6/2) gravelly fine sand, light gray (2.5Y 7/2) dry; massive; loose; 1 percent very fine and fine roots; 4 percent fine and medium distinct dark gray (10YR 4/1) and 3 percent fine and medium gray (N 5/) iron depletions with clear boundaries in the matrix; 20 percent gravel-sized, and 10 percent sand-sized seashell fragments; 7 percent gravel-sized serpulid reef fragments; nonsaline; Sodium Adsorption Ratio is less than 1; very slightly effervescent; slightly alkaline; gradual smooth boundary.
Cg2--102 to 170 cm (40 to 67 in); light olive gray (5Y 6/2) loamy fine sand, light gray (5Y 7/2) dry; massive; soft, very friable; 1 percent very fine and fine roots; 2 percent 1 cm thick strata of greenish gray (10Y 5/1) clay; 2 percent 1 cm thick strata of olive gray (5Y5/2) clay loam; 3 percent fine and medium prominent light olive brown (2.5Y 5/6) and 1 percent fine prominent strong brown (7.5YR 5/6) masses of oxidized iron with clear to sharp boundaries lining pores; 3 percent fine and medium distinct olive gray (5Y 5/2) iron depletions with diffuse boundaries in the matrix; 7 percent gravel-sized and 10 percent sand-sized seashell fragments; 5 percent gravel-sized serpulid reef fragments; nonsaline; Sodium Adsorption Ratio is about 1; very slightly effervescent; slightly alkaline; gradual smooth boundary. (Combined thickness of the Cg horizon is 104 to 165 cm [41 to 62 in].)
Cg3--170 to 203 cm (67 to 80 in); gray (5Y 6/1) gravelly fine sand, light gray (5Y 7/1) dry; massive; soft, very friable; 5 percent fine and medium distinct greenish gray (5GY 6/1) iron depletions with diffuse boundaries in the matrix; 10 percent gravel-sized and 10 percent sand-sized seashell fragments; 10 percent paragravel-sized claystone fragments; nonsaline; Sodium Adsorption Ratio is about 2; very slightly effervescent; slightly alkaline.
TYPE LOCATION: Kenedy County, Texas; from the intersection of Park Road 22 and the county line between Kleberg and Nueces Counties; 8.0 miles southwest on Park Road 22 to the pay station entrance of Padre Island National Seashore; 0.8 miles southwest on Park Road 22 to the intersection of Novillo and Bird Island Basin road; 2.1 miles west-northwest and north on Bird Island Basin road to boat ramp; 28.7 miles by boat generally west-southwest along the Gulf Intracoastal Waterway into the landcut to channel running east near the center of Potrero Grande; 600 feet east into channel; 400 feet north on mound in wildlife land. Potrero Cortado, Texas USGS topographic quadrangle; Latitude: 27 degrees, 06 minutes, 13.7 seconds N; Longitude: 97 degrees, 26 minutes, 24.7 seconds W; WGS 84; UTM Easting 654625.30m, UTM Northing 2998891.89m, UTM 14.
RANGE IN CHARACTERISTICS:
Soil Moisture: An ustic soil moisture regime bordering on udic. The soil moisture control section is dry in some or all parts for less than 120 cumulative days in normal years. A water table is present in most pedons at depths of 76 to 152 cm (30 to 60 in) throughout the year in most years.
Mean annual soil temperature: 21.7 to 22.8 degrees C (71 to 73 degrees F)
Depth to masses of oxidized iron: 0 to 25 cm (0 to 10 in)
Depth to iron depletions: 76 to 152 cm (30 to 60 in)
Depth to endosaturation: 76 to 152 cm (30 to 60 in) throughout the year in most years.
Particle-size control section (weighted average)
Clay content: 5 to 18 percent
Sand content: 70 to 95 percent
Coarse fragments consist of seashell and seashell fragments, or fragments of serpulid reefs.
A horizon
Hue: 10YR or 2.5Y
Value: 4 to 6 (5 to 7 dry)
Chroma: 2 or 3
Texture: fine sand
Clay content: 4 to 10 percent
Redox Concentration: amount-2 to 15 percent, size-fine or medium, contrast-faint to prominent, boundary-clear to sharp
Coarse fragments: 1 to 14 percent
Electrical Conductivity (dS/m): 0 to 4
Sodium Adsorption Ratio: 0 to 8
Reaction: slightly alkaline to strongly alkaline
C horizon
Hue: 10YR, 2.5Y or 5Y
Value: 5 or 6 (6 or 7 dry)
Chroma: 2 or 3
Texture: loamy fine sand, fine sandy loam or their gravelly counterparts
Clay content: 5 to 19 percent
Redox Concentration: amount-2 to 15 percent, size-fine or medium, contrast-faint to distinct, boundary-clear to sharp
Redox depletions: amount-0 to 2 percent, size-fine or medium, contrast-faint or distinct, boundary-diffuse or clear
Coarse fragments: 1 to 20 percent
Electrical Conductivity (dS/m): 0 to 4
Sodium Adsorption Ratio: 0 to 8
Reaction: slightly alkaline to strongly alkaline
Cg horizon
Hue: 2.5Y, 5Y, 10Y or 5GY
Value: 5 to 6 (6 or 7 dry)
Chroma: 1 or 2
Texture: fine sand, loamy fine sand, fine sandy loam or their gravelly counterparts
Clay content: 5 to 18 percent
Redox Concentration: amount-2 to 20 percent, size-fine to coarse, contrast-faint to prominent, boundary-clear to sharp
Redox depletions: amount-0 to 20 percent, size-fine to coarse, contrast-faint or distinct, boundary-diffuse or clear
Coarse fragments: 1 to 30 percent
Electrical Conductivity (dS/m): 0 to 4
Sodium Adsorption Ratio: 0 to 8
Reaction: neutral to strongly alkaline
COMPETING SERIES: There are no competing series in the same family. Similar soils are the
Neches (TX),
Riolomas (TX),
Sievers (TX), and
Yarborough (TX) series.
Neches and
Riolomas soils: have no seashell fragments, do not have iron depletions within 102 cm (40 in), and are in the udic moisture regime.
Sievers soils: have a fine-loamy particle size control section, are somewhat poorly drained, and are in the udic moisture regime.
Yarborough soils: are poorly drained, have SODIUM ADSORPTION RATIO of 13 or more within 102 cm (40 in) of the soil surface and have a water table within 61 cm (24 in) of the surface.
GEOGRAPHIC SETTING:
Parent material: Sandy and loamy sediments dredged from shallow bays
Landscape: Bays
Landform: mounds on spoil piles
Slope: 1 to 3 percent
Mean annual air temperature range: 22 to 23 degrees C (71 to 73 degrees F)
Mean annual precipitation range: 635 to 889 mm (25 to 35 in)
Precipitation Pattern: November through April are the driest months, with a second dry period in July. September is the wettest month.
Frost-free period: 310 to 350 days
Elevation: 0.9 to 3 m (3 to 10 ft)
Thornthwaite P-E Index: 31 to 44
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Arrada,
Baffin,
Madre,
Malaquite,
Satatton,
Tatton, and
Yarborough series.
Arrada,
Satatton and
Tatton soils: have SODIUM ADSORPTION RATIO of 13 or more within 102 cm (40 in) of the surface, and occur on lower wind tidal flat landforms.
Baffin soils: are very poorly drained, have an n-value of more than 0.7 in the upper 51 cm (20 in), and are on lower landforms under seawater.
Madre and
Malaquite soils: are poorly drained, have SODIUM ADSORPTION RATIO of 13 or more within 51 cm (40 in) of the surface, and occur on barrier flats.
Yarborough soils: are very slowly permeable and lower positions on spoil piles.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Permeability is moderate. Runoff is low. A water table is present in most pedons within a depth of 76 to 152 cm (30 to 60 in). These soils are subject to occasional flooding for very brief periods of time by high storm surge during strong tropical storms.
USE AND VEGETATION: Used for wildlife habitat. Native vegetation consists of seacoast bluestem, gulfdune paspalum, brownseed paspalum, ragweed and scattered mesquite. The ecological site is Coastal Sand, PE 31-44 (150BY648TX).
DISTRIBUTION AND EXTENT: Gulf Coast Saline Prairies (MLRA 150B in LRR T) on spoil pile areas associated with bay systems and barrier islands along the lower Gulf Coast of Texas. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Kenedy County, Texas; 2007. Series proposed for Kenedy and Kleberg Counties soil survey area, 2004. The name is from the local name of a spoil island near Baffin Bay.
REMARKS: The series was formerly included in the Ijam series, undifferentiated groups Ustifluvents, Ustorthents, or Udipsamments, or the miscellaneous areas - spoil piles.
The series was established based on the difference in family particle size and soil moisture regime.
Diagnostic horizons and features recognized in this pedon are:
Aquic conditions: 76 to 203 cm (30 to 80 in). (Cg1, Cg2 and Cg3 horizons)
Particle size control section: 25 to 102 cm (10 to 40 in). (A2, C and Cg1 horizons)
Ochric epipedon: 0 to 46 cm (0 to 18 in). (A1 and A2 horizons)
Masses of oxidized iron: 0 to 203 cm (0 to 80 in). (A1, A2, C, Cg1, Cg2 and Cg3 horizons)
Iron depletions: depleted matrix at 71 to 203 cm (28 to 80 in). (Cg1, Cg2 and Cg3 horizons)
Endosaturation: The zone of saturation at 76 to 203 cm (30 to 80 in) in most years throughout the year.
ADDITIONAL DATA: Particle-size analysis on seven pedons, and salinity and sodicity tests on ten pedons performed at the soil survey project office.
Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.