LOCATION LAEWEST            TX

LAEWEST SERIES

TAXONOMIC CLASS: Fine, smectitic, hyperthermic Typic Hapluderts

TYPICAL PEDON: Laewest clay, from a microlow, on southeast-facing, plane, 0.1 percent slope in rangeland at an elevation of 10.7 m (35 ft)(Colors are for moist soil unless otherwise stated.)

A1--0 to 25 cm (0 to 10 in); black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; moderate fine subangular blocky structure; very hard, firm; common very fine and few fine and medium roots; common fine and few medium pores; neutral; clear wavy boundary.

A2--25 to 46 cm (10 to 18 in); black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; moderate fine and medium angular blocky structure; very hard, firm; common very fine and few fine and medium roots; common fine and few medium pores; common pressure faces; few dark gray worm casts; neutral; gradual wavy boundary. (combined thickness of the A horizons is 30 to 61 cm [12 to 24 in])

Bss1--46 to 74 cm (18 to 29 in); black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; moderate medium and coarse angular blocky structure; very hard, firm; few very fine, fine and medium roots; common fine and medium pores; many pressure faces and common prominent slickensides; few dark gray worm casts; neutral; gradual wavy boundary.

Bss2--74 to 94 cm (29 to 37 in); very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry; moderate medium and coarse angular blocky structure; very hard, very firm; few very fine and fine roots; few fine and medium pores; many pressure faces and common prominent slickensides; few fine iron-manganese concretions; few gray worm casts; slightly alkaline; clear wavy boundary. (combined thickness of the Bss horizons is 25 to 114 cm [10 to 45 in])

Bkss1--94 to 117 cm (37 to 46 in); dark gray (10YR 4/1) clay, gray (10YR 5/1) dry; moderate coarse angular blocky structure parting to moderate fine and medium angular blocky; very hard, very firm; few very fine and fine roots; few fine and medium pores; many pressure faces and prominent slickensides; few fine iron-manganese concretions; about 3 percent concretions of calcium carbonate mainly less than 1 cm (1/4 in) in diameter; few gray worm casts; slightly effervescent; moderately alkaline.

Bkss2--117 to 137 cm (46 to 54 in); gray (10YR 5/1) clay, gray (10YR 6/1) dry; moderate coarse angular blocky structure parting to weak fine and medium angular blocky; very hard, very firm; few fine roots; few fine and medium pores; common medium faint grayish brown (10YR 5/2) redox depletions; common pressure faces and prominent slickensides; few fine iron-manganese concretions; about 2 percent concretions of calcium carbonate 1/2 to 1 cm (1/8 to 1/4 in) in diameter; few dark gray worm casts; slightly effervescent; moderately alkaline. (combined thickness of the Bkss horizons is 25 to 61 cm [10 to 24 in])

BCkss--137 to 203 cm (54 to 80 in); light gray (10YR 7/2) clay, very pale brown (10YR 8/2) dry; weak medium and coarse angular blocky structure; very hard, very firm; few fine roots; few fine pores; common fine and medium distinct yellow (10YR 7/6) redox concentrations; common pressure faces and prominent slickensides; few fine iron-manganese concretions; about 2 percent concretions of calcium carbonate 1/2 to 1 cm (1/8 to 1/4 in) in diameter; few dark gray worm casts; slightly effervescent; moderately alkaline.

TYPE LOCATION: Jackson County, Texas; from the intersection of Farm Road 234 and Farm Road 616 in Vanderbilt, 1.1 miles southwest on Farm Road 616, 0.2 of a mile south on paved private road, 200 feet west of road in rangeland in a micro-depression. Kamey USGS quad; Longitude is 96 degrees, 37 minutes, 59 seconds W; Latitude is 28 degrees, 48 minutes, 44 seconds N; NAD 83

RANGE IN CHARACTERISTICS: The solum thickness is more than 200 cm (80 in). Iron-manganese concretions, mainly less than 1/4 inch in diameter, range from none to few throughout, but commonly are in the lower part. This is a cyclic soil and undisturbed areas have gilgai microrelief with microhighs 15 to 30 cm (6 to 12 in) higher than microlows. Distance from the center of the microhighs to the center of the microlows ranges from about 1.2 to 4.9 m (4 to 16 ft). The microhigh makes up about 20 percent, the intermediate, or area between the knoll and depression about 50 percent, and the microlow about 30 percent. The amplitude of waviness between mollic colored materials in the upper part of the solum and the higher value colors in the lower part ranges from about 30 to 150 cm (12 to 60 in). The chimneys of high value materials on microhighs make up 2 to 5 percent of the surface area. They are mainly 0.6 to 2.4 m (2 to 8 ft) long and 0.2 to 0.6 m (1/2 to 2 ft) wide. When dry, the soil has cracks 1 to 5 cm (about 1/2 to 2 in) wide at the surface and commonly 1 cm (1/2 inch) wide cracks extend to a depth of 1.2 m (4 ft) during the summer. The cracks remain open for less than 90 cumulative days in most years. Slickensides begin at a depth of 30 to 61 cm (12 to 24 in) and extend throughout the solum. The angle of the slickensides ranges from about 10 to 65 degrees from horizontal and tend to be more vertical in microhighs than in microlows. Some pedons have an overwash of calcareous clay or silty clay 20 to 51 cm (8 to 20 in) thick.

Soil Moisture: An udic soil moisture regime. The soil moisture control section is not dry in some or all parts for as long as 90 cumulative days in normal years. July and August are the driest months, while April through June and September through November is the wettest.

Mean annual soil temperature: 22 to 23.5 (72 to 74 degrees F).

Particle-size control section (weighted average)
Clay content: 45 to 60 percent clay and more than 28 percent silt.

A Horizon
(microlow)
Hue: 10YR, 2.5Y or 5Y
Value: 2 or 3
Chroma: 1
Texture: clay but silty clay is allowed for moderately alkaline overwash phases.
Redox concentrations: amount-0 to 5 percent, shades-yellow or brown
Iron-manganese concentrations: amount-0 to 1 percent, size- up to 3 mm, kind-concretions
Reaction: slightly acid or neutral

A Horizon
(microhigh)
Hue: 10YR, 2.5Y or 5Y
Value: 3 to 5
Chroma: 1 to 3
Texture: clay but silty clay is allowed for moderately alkaline overwash phases.
Identifiable secondary carbonate: amount-0 to 2, size-2 mm to 1 cm; kind-nodules or masses
Effervescence: none to slight
Reaction: slightly acid to slightly alkaline

Bss Horizon
(microlow)
Hue: 10YR, 2.5Y or 5Y
Value: 2 or 3
Chroma: 1
Identifiable secondary carbonate: amount-0 to 2, size-2 mm to 1 cm; kind-nodules or masses
Redox concentrations: amount-0 to 5 percent, shades-yellow or brown
Iron-manganese concentrations: amount-0 to 1 percent, size- up to 3 mm, kind-concretions
Reaction: slightly acid to slightly alkaline

Bss Horizon
(microhigh)
Hue: 10YR, 2.5Y or 5Y
Value: 4 to 6
Chroma: 1 to 4
Identifiable secondary carbonate: amount-0 to 5, size-2 mm to 1 cm; kind-nodules or masses
Reaction: slightly acid to slightly alkaline

Bkss Horizon
(microlow and michrohigh)
Hue: 10YR, 2.5Y, or 5Y (Spots of very dark gray or black soil materials from horizons above range from none to few.)
Value: 4 to 6
Chroma: 1 or 2
Redox concentrations: amount-1 to 5 percent, shades-yellow or brown
Redox depletions: amount-0 to 2 percent, shades-gray
Iron-manganese concentrations: amount-0 to 1 percent, size- up to 3 mm, kind-concretions
Identifiable secondary carbonate: amount-2 to 10 percent, size-2mm to 3 cm, kind-concretions, threads, or masses
Effervescence: very slight to strong
Reaction: slightly alkaline or moderately alkaline

BCkss, BCk or 2BC (where present) Horizon
(microlow and microhigh)
Hue: 10YR, 2.5Y, or 5Y
Value: 4 to 7
Chroma: 2 to 6
Texture: clay loam or clay
Redox concentrations: amount-2 to 20 percent, shades-yellow or brown
Redox depletions: amount-0 to 2 percent, shades-gray
Iron-manganese concentrations: amount-0 to 1 percent, size- up to 3 mm, kind-concretions
Identifiable secondary carbonate: amount-2 to 10 percent, size-2mm to 3 cm, kind-concretions, threads, or masses
Effervescence: very slight to strong

2C Horizon (where present)
Hue: hue of 7.5YR to 5Y
Value: 5 to 7
Chroma: 1 to 4
Texture: loam to clay
Effervescence: slight to violent

COMPETING SERIES: These are the Francitas (TX), Ganado (TX), and Lake Charles (TX) series. Similar soils are the Bacliff (TX), Pledger (TX), and Victoria (TX) series.
Francitas soils: are saline
Ganado soils: mollic colors to a depth greater than 100 cm (40 in) throughout the pedon.
Lake Charles soils: less amplitude of waviness; are moist in the moisture control section for slightly longer periods; allow hue redder than 10YR in the lower horizon.
Bacliff soils: have colors with value greater than 3 throughout; are moist in the moisture control section for slightly longer periods
Pledger soils: have a very-fine particle-size control section.
Victoria soils: are typically calcareous throughout; have cracks that remain open more than 90 days in most years.

GEOGRAPHIC SETTING:
Parent material: clayey flood basin deposits on alluvial plains or deltas of the Beaumont Formation of Pleistocene Age
Landscape: flat coastal plains
Landform: broad flats
Slope: dominantly less than 1 percent but range to 8 percent on side slopes of along drainageways
Mean annual air temperature range: 21 to 22 degrees C (70 to 72 degrees F).
Mean annual precipitation range: 914 to 1118 mm (36 to 44 in)
Precipitation Pattern: Precipitation falls mostly from April through December. January through March are the driest months
Frost-free period: 280 to 300 days
Elevation: 3 to 30.5 m (10 to 100 ft)
Thornthwaite annual P-E indices: 46 to 60

GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Bacliff (TX) and Francitas (TX) series and the Dacosta (TX), Edna (TX), and Faddin (TX) soils.

Bacliff and Francitas soils: on lower slightly depressional landform.
Dacosta soils: on a slightly lower or similar positions
Edna and Faddin soils: are on similar positions. In addition, Dacosta, Edna, and Faddin soils have loamy surface layers and argillic horizons.

DRAINAGE AND PERMEABILITY: Laewest soils are moderately well drained. The permeability is very slow. Water enters the soil rapidly when it is dry and cracked, but very slowly when the soil is wet and the cracks are sealed. Runoff is low on 0 to 1 percent slopes, medium on 1 to 3 percent slopes, high on 3 to 5 percent slopes and very high on 5 to 8 percent slopes.

USE AND VEGETATION: The soil is used mainly for rangeland and cropland. The most common crops grown are grain sorghum, corn, rice, and cotton. Turf grasses are also grown. Climax rangeland vegetation consists mainly of little bluestem, indiangrass, eastern gamagrass, switchgrass, big bluestem, and paspalums. Trees include liveoak, elm, hackberry, huisache, and mesquite along fence rows, drainageways and in scattered motts. (Ecological site name: Blackland 24-44" Pz; Ecological site number: R150AY526TX)

DISTRIBUTION AND EXTENT: The Gulf Coast Prairies (MLRA 150A; LRR T) of Texas west of the Colorado River to about the central part of Refugio County.
MLRA OFFICE RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Jackson County, Texas; 1991.

REMARKS: These soils were previously included with the Lake Charles series. The name Laewest is coined.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon: 0 to 94 cm (0 to 37 in) (A1, A2, Bss1, Bss2 and horizons)

Vertisol feature: deep wide cracks that open and close one or more times a year and remain open for less than 90 cumulative days in most years; slickensides from depth of 46 to 203 cm (18 to 80 in)

ADDITIONAL DATA: TAMU data S82TX-481-002, S82TX-481-001. NSSL data S89TX469-008,009,010,011,012,013,014 (Texas Vertisol Study)