LOCATION EKAL TX

Established Series
Rev. CWW-RM
01/2018

EKAL SERIES

The Ekal series consists of very deep, somewhat poorly drained, very slowly permeable saline soils formed in intermittent clayey lakebed deposits derived from limestone. These nearly level depressional and playa soils occur on depressions on dissected plateaus. Slopes range from 0 to 1 percent. Mean annual temperature is about 17.2 degrees C (63 degrees F), and mean annual precipitation is about 457 mm (18 in).

TAXONOMIC CLASS: Fine, smectitic, calcareous, thermic Vertic Epiaquolls

TYPICAL PEDON: Ekal clay--0.5 percent slopes in a dry lakebed. (Colors are for dry soil unless otherwise stated. When described, the soil was moist throughout.)

A--0 to 20 cm (0 to 8 in); gray (10YR 5/1) clay, very dark grayish brown (10YR 3/2) moist; moderate fine to medium subangular blocky structure; very hard, very firm, very sticky and very plastic; common fine and medium roots; calcareous; moderately alkaline; clear smooth boundary.

An--20 to 38 cm (8 to 15 in); gray (10YR 5/1) clay, very dark gray (10YR 3/1) moist; moderate fine angular blocky structure; extremely hard, very firm, very sticky and very plastic; common fine roots; calcareous; moderately alkaline; clear smooth boundary. (Combined thickness of the A horizon is 25 to 50 cm [10 to 20 in].)

Bn1--38 to 56 cm (15 to 22 in); light gray (10YR 6/1) clay, dark gray (10YR 4/1) moist; moderate fine and medium angular blocky structure; vertical cracks filled with soil from above are one-third inch wide; extremely hard, very firm, very sticky and very plastic; calcareous; moderately alkaline; gradual wavy boundary.

Bn2--56 to 91 cm (22 to 36 in); light gray (10YR 6/1) clay, dark gray (10YR 4/1) moist; moderate fine angular blocky structure; extremely hard, very firm, very sticky and very plastic; few white aggregates of salts one-eighth to one-fourth inch in diameter; few fine faint brown (7.5YR 4/4), moist, mottles and streaks along root channels; calcareous; moderately alkaline; gradual wavy boundary.

Bn3--91 to 122 cm (36 to 48 in); gray (10YR 6/1) clay, gray (10YR 5/1) moist; moderate medium angular blocky structure; extremely hard, very firm, very sticky and very plastic; few white masses of salts one-eighth to one-fourth inch across; calcareous; moderately alkaline; gradual wavy boundary. (Combined thickness of the Bn horizons is 50 to 127 cm (20 to 50 in].)

Cn--122 to 145 cm (48 to 57 in); light gray (10YR 7/2) clay loam, light brownish gray (10YR 6/2) moist; moderate medium subangular blocky structure; extremely hard, very firm, sticky and plastic; calcareous; moderately alkaline; gradual wavy boundary. (Thickness of the Cn horizons is 51 to 103 cm [20 to 40 in].)

Cny--145 to 203 cm (57 to 80 in); pale yellow (2.5Y 8/2) clay loam, light gray (2.5Y 7/2) moist; extremely hard, very firm, sticky and plastic; 15 percent gypsum crystals; calcareous; moderately alkaline.

TYPE LOCATION: Reagan County, TX; from the intersection of Highways 67 and 137 in Big Lake, 2.0 miles south on Highway 137, 180 yards west in rangeland.

USGS topographic quadrangle: Big Lake, TX;
Latitude: 31 degrees, 9 minutes, 43.72 seconds N;
Longitude: 101 degrees, 28 minutes, 9.17 seconds W;
Datum: WGS84.

UTM Easting 264639.58 m,
UTM Northing 3450197.24 m,
UTM Zone 14.

RANGE IN CHARACTERISTICS:
Depth to cambic horizon: 25 to 50 cm (10 to 20 in)
Depth to salt accumulations: 15 to 25 cm (6 to 10 in)
Depth to gypsum accumulations: 100 to 152 cm (40 to 60 in)
Thickness of the mollic epipedon: 25 to 50 cm (10 to 20 in)
Vertic features: 38 to 122 cm (15-48 in)

Particle-size control section (weighted average)
Clay content: 40 to 55 percent

A Horizon
Hue: 10YR
Value: 4 or 5, 1 to 3 moist
Chroma: 1 or 2, 1 to 3 moist
Texture: clay
Clay content: 40 to 55 percent
Calcium carbonate equivalent: 15 to 25 percent
Gypsum: 0 to 1 percent
Electrical conductivity (decisiemens per meter): 8 to 16
Sodium Adsorption Ratio: 12 to 25
Effervescence: strong or violent
Reaction (pH): slightly or moderately alkaline (7.4 to 8.4)

Bn Horizon
Hue: 10YR
Value: 5 or 6
Chroma: 1 or 2
Texture: clay or silty clay
Clay content: 40 to 55 percent
Calcium carbonate equivalent: 20 to 35 percent
Gypsum: 1 to 5 percent
Electrical conductivity (decisiemens per meter): 16 to 32
Sodium Adsorption Ratio: 25 to 40
Effervescence: strong or violent
Reaction (pH): slightly or moderately alkaline (7.4 to 8.4)

Cn or Cny Horizon
Hue: 10YR or 2.5Y
Value: 6 to 8
Chroma: 2 or 3
Texture: clay loam
Clay content: 27 to 40 percent
Calcium carbonate equivalent: 15 to 35 percent
Gypsum: 10 to 30 percent
Electrical conductivity (decisiemens per meter): 16 to 32
Sodium Adsorption Ratio: 20 to 30
Effervescence: strong or violent
Reaction (pH): slightly or moderately alkaline (7.4 to 8.4)

COMPETING SERIES: There are no other soils in this family. Similar soils are Balmorhea and Tobosa series.
Balmorhea soils: average less than 35 percent clay in the textural control section.
Tobosa soils: have cracks that are at least 1 cm wide at 51 cm (20 in) and extend to the surface.

GEOGRAPHIC SETTING:
Parent material: intermittent clayey lakebed deposits derived from limestone
Landscape: dissected plateaus
Landform: depressions
Slope: 0 to 1 percent
Mean annual precipitation: 406 to 508 mm (16 to 20 in)
Thornthwaite P-E Index: 23 to 26
Mean annual air temperature: 16.7 to 18.9 degrees C (62 to 66 degrees F)
Frost-free period: 210 to 240 days
Elevation: 792.5 to 823 m (2600 to 2700 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Angelo, Conger, Ector, Hollomex, Reagan, Reeves, and Tobosa soils.
Angelo soils: formed in valley fill material where water does not accumulate
Conger soils: are shallow to pertrocalcic horizon that occur on ridges
Ector soils: are shallow to lithic contact that occurs on ridges and sidelsopes
Hollomex and Reeves soils: formed in aeolian gypsiferous materials and occupy slightly higher positions
Reagan soils: are in higher positions and have developed in light colored loamy materials
Tobosa soils: are in higher positions and have wedge-shaped peds and slickensides.

DRAINAGE AND PERMEABILITY:
Drainage class: Somewhat poorly.
Permeability class: Very slow
Runoff: negligible.
Wetness: soil is occasionally ponded or the surface is saturated for long periods during the months of May to September.

USE AND VEGETATION: Used for rangeland. The vegetation consists of small salt-tolerant plants.

DISTRIBUTION AND EXTENT: Reagan County, Texas. The series is of minor extent.

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

SERIES ESTABLISHED: Reagan County, Texas; 1989.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 25 to 100 in. (An, Bn1, Bn2, and Bn3 horizons)
Mollic epipedon: 0 to 38 cm (0 to 15 in) (A and An horizons)

Cambic horizon: 38 to 122 cm (15 to 48 in) (Bn1, Bn2 and Bn3 horizons)

ADDITIONAL DATA: The Ekal pedon was sampled at the type location. Electrical conductivity, sodium absorption ratio, calcium carbonate equivalent, and gypsum were tested. Texas A&M University laboratory sample numbers are C4117 to C4123.

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

National Cooperative Soil Survey
U.S.A.