LOCATION ARRADA                  TX

Established Series
JKW-NIH-RM
09/2015

ARRADA SERIES

The Arrada series consists of very deep, poorly drained, moderately slowly permeable soils on wind tidal flats. These soils formed in extremely saline loamy alluvial sediments of Holocene age. Slope ranges from 0 to 1 percent. Mean annual air temperature is about 22 degrees C (72 degrees F) and mean annual precipitation is about 686 mm (27 in).

TAXONOMIC CLASS: Fine-loamy, mixed, semiactive, calcareous, hyperthermic Typic Halaquepts

TYPICAL PEDON: Arrada sandy clay loam, on a nearly level 0 to 1 percent slope on a wind tidal flat at an elevation of 0.6 m (2 ft) above sea level. (Colors are for moist soil unless otherwise stated.)

Anzg--0 to 13 cm (0 to 5 in); gray (5Y 5/1) sandy clay loam, gray (5Y 6/1) dry; weak medium platy structure; slightly hard, friable; few fine vesicular pores; 50 percent medium platy salt masses; 3 percent fine and medium distinct light olive brown (2.5Y 5/4) masses of oxidized iron with sharp boundaries lining pores and between plates; strongly saline; strongly effervescent; strongly alkaline; abrupt smooth boundary. (Anzg horizon is 8 to 20 cm [3 to 18 in] thick.)

Bnzg1--13 to 41 cm (5 to 16 in); gray (5Y 5/1) sandy clay loam, gray (5Y 6/1) dry; weak medium prismatic structure parting to weak fine and medium subangular blocky; slightly hard, friable; 2 percent fine calcium carbonate nodules; 2 percent fine and medium salt masses; 2 percent medium prominent dark brown (10YR 3/3) masses of oxidized iron with diffuse boundaries in the matrix; strongly saline; strongly effervescent; strongly alkaline; clear smooth boundary.

Bnzg2--41 to 81 cm (16 to 32 in); gray (5Y 5/1) sandy clay loam, gray (5Y 6/1) dry, weak medium and coarse subangular blocky structure; slightly hard, friable; 2 percent fine and medium salt masses; 2 percent black iron-manganese concretions; 1 percent fine distinct light olive brown (2.5Y 5/4) masses of oxidized iron with diffuse boundaries in the matrix; strongly saline; strongly effervescent; strongly alkaline; clear smooth boundary. (Combined thickness of the Bnzg horizons is 38 to 117 cm [15 to 46 in])

BCnzg1--81 to 137 cm (32 to 54 in); light gray (5Y 7/2) sandy clay loam, pale yellow (5Y 8/2) dry; weak medium and coarse subangular blocky structure; slightly hard, friable; 1 percent fine calcium carbonate nodules; 2 percent fine salt masses; 20 percent medium prominent yellowish brown (10YR 5/6) masses of oxidized iron with clear boundaries in the matrix; strongly saline; violently effervescent; strongly alkaline; clear smooth boundary. (Combined thickness of the BCnzg horizons is 41 to 114 cm [16 to 45 in].)

BCnzg2--137 to 203 cm (54 to 80 in); greenish gray (5GY 6/1) sandy clay loam, light greenish gray (5GY 7/1) dry; weak fine and medium subangular blocky structure; slightly hard, friable; 1 percent fine nodules of calcium carbonate; 1 percent fine salt masses; strongly saline; violently effervescent; strongly alkaline.

TYPE LOCATION: Willacy County, Texas; from the intersection of U.S. Highway 77 bypass and Texas Highway 186 in Raymondville; 16.3 miles east on Texas highway 186 to Farm Road 497; 16.3 miles east on Farm Road 497 to Farm Road 606 in Port Mansfield; 0.8 mile north on Farm Road 606 to end of road; 0.5 mile west along fence line; 31 m (100 ft) south on wind tidal flat; Port Mansfield, Texas USGS topographic quadrangle; Latitude: 26 degrees, 34 minutes, 11.7 seconds N; Longitude: 97 degrees, 26 minutes, 14.5 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil Moisture: An aquic soil moisture regime. Although rainfall amounts are that of an ustic moisture regime, these soils remain saturated throughout in most years due to location on the landscape. The top of a permanent water table is at a depth of 30 to 61 cm (12 to 24 in) throughout the year in normal years, and the soil is subject to frequent flooding by high tides, storm surges or heavy rains associated with tropical storms.
Mean annual soil temperature: 22.2 to 24.5 degrees C (74 to 76 degrees F)
Electrical Conductivity (dS/m): 60 to 175
Sodium Adsorption Ratio: 60 to 125
Depth to masses of oxidized iron: 0 to 25 cm (0 to 10 in)
Depth to iron depletions or depleted matrix: 0 to 25 cm (0 to 10 in)
Depth to endosaturation: 31 to 91 cm (12 to 36 in)
Depth to Salic horizon: 10 to 40 cm (4 to 16 in)

Particle-size control section (weighted average)
Clay content: 18 to 27 percent
Sand content: 60 to 80 percent
CEC/Clay ratio: .24 to .40 (Semiactive)

Anzg horizon:
Hue: 2.5Y or 5Y
Value: 4 to 7
Chroma: 1 or 2
Texture: fine sandy loam or sandy clay loam
Clay content: 11 to 32 percent
Redox concentrations: amount-1 to 15 percent; size-fine or medium; contrast-faint to prominent; boundaries-clear or sharp; shades-brown or yellow
Redox depletions: amount-0 to 7 percent; size-fine or medium; contrast-faint or distinct; boundary-diffuse or clear; shades-gray
Reaction: slightly alkaline to very strongly alkaline

Bnzg horizon:
Hue: 2.5Y, 5Y, 10Y or 10GY
Value: 4 to 8
Chroma: 1 or 2
Texture: fine sandy loam or sandy clay loam, or clay loam (textures are variable, and can be stratified with loamy fine sand)
Clay content: 14 to 32 percent
Redox concentrations: amount-1 to 25 percent; size-fine or medium; contrast-faint or distinct; boundaries-clear or sharp; shades-brown or yellow
Redox depletions: amount-1 to 20 percent; size-fine or medium; contrast-faint; boundary-diffuse or clear; shades-gray
Reaction: slightly alkaline to very strongly alkaline

BCnzg horizon:
Hue: 5Y, 10Y, 5GY or 10GY
Value: 4 to 8
Chroma: 1 or 2
Texture: loamy fine sand, fine sandy loam or sandy clay loam
Clay content: 9 to 25 percent
Redox concentrations: amount-0 to 10 percent; size-fine or medium; contrast-faint to prominent; boundaries-clear or sharp; shades-brown or yellow
Redox depletions: amount-1 to 25 percent; size-fine to coarse; contrast-faint or distinct; boundary-diffuse or clear; shades-gray or green
Reaction: slightly alkaline to very strongly alkaline

COMPETING SERIES: There are no competing series in the same family. Similar soils are the Barrada (TX), Cedarlake (TX), Latina (TX), Malaquite (TX), Satatton (TX), Saucel (TX), Sejita (TX), Tatton (TX), Topo (TX), Vanguard (CA), and Yarborough (TX) series.
Barrada soils: are in the fine particle size family.
Cedarlake and Vanguard soils: have a thermic temperature regime.
Latina soils: have a calcic horizon.
Malaquite soils: are in the sandy particle size family.
Satatton and Tatton soils: are Sodic Psammaquents.
Saucel, Topo, and Yarborough soils: are in the coarse-loamy particle size family.
Sejita sois: are in the fine-silty particle size family.

GEOGRAPHIC SETTING:
Parent material: Loamy eolian deposits and storm washover sediments of Holocene age.
Landform: Wind-tidal flats and elongated depressions
Slope: 0 to 1 percent
Mean annual air temperature range: 22 to 24 degrees C (71 to 75 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 to 1.5 m (0 to 5 ft)
Thornthwaite P-E Index: 31 to 36

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barrada, Lalinda, Latina, Saucel, and Sauz series.
Barrada soils: occur on a similar to slightly lower landform.
Lalinda soils: do not have aquic conditions and are a higher landform on coastal ridges.
Latina and Saucel soils: occur on a slightly higher landform above the wind-tidal flats.
Sauz soils: have a natric horizon and are on a higher landform on low coastal terraces.

DRAINAGE AND PERMEABILITY: Poorly drained. Permeability is moderately slow. Runoff is negligible. A permanent water table is at a depth of 30 cm to 61 cm (12 to 24 in). These soils are frequently flooded for brief periods with salt water, which occur during times of high wind that pushes water onto the wind-tidal flats, storm surges, and heavy rains associated with tropical storms.

USE AND VEGETATION: Mostly used for wildlife habitat or recreation. These soils are essentially barren of vegetation except for sparse salicornia and sesuvium species at the higher elevations. The surface will often have a thin algal mat. Halophytic vegetation consisting of saltwort and glassworts occur for short periods after recent inundation. The surface salinity rises as the surface dries, and eventually becomes toxic to the plants. The ecological site is Tidal Flat, PE 31-44 (R150BY416TX).

DISTRIBUTION AND EXTENT: Gulf Coast Saline Prairie (MLRA 150B in LRR T) of south Texas. The series is of moderate extent.

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

SERIES ESTABLISHED: Willacy County, Texas; 1980.

REMARKS: Classification change from Typic Salorthids to Typic Aquisalids 05/1995 based on application of the Keys to Soil Taxonomy, Sixth Edition. Classification change from Typic Aquisalids to Typic Halaquepts 10/1998 based on application of the Keys to Soil Taxonomy, Eighth Edition.

Diagnostic horizons and features recognized in this pedon are:

Particle size control section: 25 to 102 cm (10 to 40 in). (Bnzg1, Bnzg2 and BCnzg1 horizons)
Ochric epipedon: 0 to 13 cm (0 to 5 in). (Anzg horizon)
Masses of oxidized iron: 0 to 137 cm (0 to 54 in). (Anzg, Bnzg1, Bnzg2 and BCnzg1 horizons)
Iron depletions or reduced matrix: 0 to 203 cm (0 to 80 in) (Anzg, Bnzg1, Bnzg2, BCnzg1 and BCnzg2 horizons)
Salic Horizon: 13 to 203 cm (5 to 80 in). (Bnzg1, Bnzg2, BCnzg1, and BCnzg2 horizons)
Endosaturation: The zone of saturation at 31 to 61 cm (12 to 24 in) for at least two months in most years. (Bnzg1, Bnzg2, BCnzg1 and BCnzg2 horizons)
Aquic Conditions: These soils remains saturated and have reducing conditions for at least one month in most years from 31 to 203 cm (12 to 80 in). (Bnzg1, Bnzg2, BCnzg1 and BCnzg2 horizons)

ADDITIONAL DATA: Texas Highway Department data from type location S78TX-489-003. Additional NSSL data from Kenedy County, Texas on sample numbers S98TX-261-001, S98TX-261-002, and S98TX-261-003.

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

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National Cooperative Soil Survey
U.S.A.