LOCATION MOWATA                  LA+TX

Established Series
DRM-JKW-RM
05/2014

MOWATA SERIES


The Mowata series consists of very deep, poorly drained, very slowly permeable soils that formed in loamy and clayey fluviomarine deposits of late Pleistocene age. These nearly level soils occur on broad flats along drainageways. Slope ranges from 0 to 1 percent. Mean annual precipitation is about 1549 mm (61 in), and mean annual air temperature is about 22 degrees C (71 degrees F).

TAXONOMIC CLASS: Fine, smectitic, thermic Typic Glossaqualfs

TYPICAL PEDON: Mowata silt loam--in a cultivated rice field. (Colors are for moist soils unless otherwise stated.)

Ap--0 to 13 cm (0 to 5 in); dark grayish brown (10YR 4/2) silt loam; weak fine granular structure; friable; many very fine and fine roots; common fine distinct dark yellowish brown (10YR 4/6) masses of iron accumulation with clear boundaries along roots; strongly acid; clear smooth boundary. (10 to 20 cm [4 to 8 in] thick)

Eg--13 to 36 cm (5 to 14 in); grayish brown (10YR 5/2) silt loam; weak fine subangular blocky structure; friable; many very fine and fine roots; common fine distinct dark yellowish brown (10YR 4/6) masses of iron accumulation with clear boundaries along roots; strongly acid; gradual irregular boundary. (15 to 51 cm [6 to 20 in] thick)

Btg/Eg--36 to 56 cm (14 to 22 in); about 70 percent dark grayish brown (10YR 4/2) silty clay loam (Btg), about 30 percent tongues of grayish brown (10YR 5/2) silt loam E material; moderate medium subangular blocky structure; firm; few fine and very fine roots; common distinct dark gray (10YR 4/1) clay films and coatings on surfaces of peds; common medium and coarse distinct dark yellowish brown (10YR 4/6) masses of iron accumulation; very strongly acid; gradual wavy boundary. (15 to 51 cm [6 to 20 in] thick)

Btgl--56 to 86 cm (22 to 34 in); grayish brown (10YR 5/2) silty clay; moderate medium subangular blocky structure; firm; many distinct very dark grayish brown (10YR 3/2) clay films and coatings on surfaces of peds; many medium and coarse distinct dark yellowish brown (10YR 4/6) masses of iron accumulation; very strongly acid; gradual wavy boundary.

Btg2--86 to 114 cm (34 to 45 in); gray (10YR 5/1) silty clay; moderate medium subangular blocky structure; firm; many faint dark gray (10YR 4/1) clay films and coatings on surfaces of peds; many medium and coarse prominent dark yellowish brown (10YR 4/6) and yellowish brown (10YR 5/6) masses of iron accumulation; moderately acid; gradual wavy boundary.

Btg3--114 to 130 cm (45 to 51 in); gray (2.5Y 6/1) silty clay; moderate medium subangular blocky structure; firm; few prominent dark gray (10YR 4/1) clay films and coatings on surfaces of peds; many medium and coarse prominent light olive brown (2.5Y 5/6) masses of iron accumulation; slightly acid; gradual wavy boundary. (Combined thickness of the Btg horizons ranges from 71 to 127 cm [28 to 50 in])

BCssg--130 to 157 cm (51 to 62 in); gray (5Y 5/1) silty clay; weak medium subangular blocky structure; firm; common distinct slickensides; common medium moderately cemented black and brownish iron-manganese concretions; many medium and coarse prominent light olive brown (2.5Y 5/6) masses of iron accumulation; neutral; gradual wavy boundary. (25 to 51 cm [10 to 20 in])

Ckssg--157 to 229 cm (62 to 90 in); gray (5Y 6/1) silty clay; massive; firm: common distinct slickensides; many medium moderately cemented black and brownish iron-manganese concretions; many coarse prominent yellowish brown (10YR 5/8) and brownish yellow (10YR 6/8) and few fine prominent strong brown (7.5YR 5/6) masses of iron accumulation; common fine and medium calcium carbonate concretions; slightly alkaline; gradual wavy boundary.

TYPE LOCATION: Acadia Parish, Louisiana; 1.7 miles northwest of Crowley; 900 feet north and 75 feet east of the southwest corner of sec. 19, T. 9 S., R. 1 E.; USGS Crowley West, LA. topographic quadrangle; Lat. 30 degrees, 14 minutes, 52 seconds N; Long. 92 degrees, 24 minutes, 47 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:

Soil Moisture: An aquic soil moisture regime.
Thickness of the solum ranges from 152 to 203 cm (60 to 80 in) or more.
Glossic materials of silt loam texture in the Btg/Eg horizon range from 1 cm to 3 cm (1/2 inch to 1 in) in width.
Slickensides are within 152 cm (60 in) of the soil surface.

Mean annual soil temperature: 19.9 to 21.7 degrees C (68 to 71 degrees F)

Particle-size control section (weighted average)
Clay content: 35 to 50 percent

Ap or A Horizon
Hue: 10YR
Value: 3 to 5 (Where value is 3 the A or Ap horizon is less than 15 cm [6 in] thick)
Chroma: 1 or 2
Texture: silt loam
Redox concentrations: amount-none to common, shades-brown
Reaction(pH): strongly acid to neutral.

Eg Horizon
Hue: 10YR
Value: 4 to 6
Chroma: 1 or 2
Texture: silt loam
Redox concentrations: amount-none to common, shades- brown or black
Reaction(pH): strongly acid to neutral

Btg/Eg, Btg, and BCssg Horizons
Hue: 10YR to 5Y
Value: 4 to 6
Chroma: 1 or 2
Texture: silty clay loam, clay loam, or silty clay
Slickensides: amount-none to common; distinctness-faint or distinct (Slickensides are common in BCssg horizon)
Ped coatings: amount-none to common; color dark gray or very dark gray, location-faces of peds
Redox concentrations: amount-few to many, shades-brown or black
Redox depletions: amount-none to common, shades-gray
Identifiable secondary carbonate: amount-none to many, kind-concretions, location-mostly in BCssg horizon
Exchangeable Sodium Percentage: 8 to 15
Reaction(pH): very strongly acid to moderately acid in the upper horizons, and from moderately acid to moderately alkaline in the lower horizons.

Cg, Cssg, or Ckssg Horizons
Hue: 10YR to 5Y or N
Value: 5 to 7
Chroma: 1 to 5
Texture: silty clay loam, clay loam, silty clay or clay
Slickensides: amount-none to common; distinctness-faint or distinct (Slickensides are common in Cssg or Csskg horizons)
Redox concentrations: amount-few to many, shades-brown or black
Identifiable secondary carbonate: amount-none to many, kind-concretions,
Reaction(pH): slightly alkaline or moderately alkaline

COMPETING SERIES: These are the Derly (TX) and Encrow (LA) series in the same family. Similar soils are Aris (TX) and Wrightsville (AR) series.
Derly soils: do not have slickensides and have exchangeable sodium less than 8 in the lower B horizons
Encrow soils: have a lithological discontinuity in the subsoil
Aris soils: are not alkaline in the lower horizons; have red redox concentrations in the argillic horizon.
Wrighstville soils: mixed mineralogy

GEOGRAPHIC SETTING:
Parent material: loamy fluviomarine deposits of late Pleistocene age
Landscape: coastal plains
Landform: broad flats along drainageways
Slope: 0 to 1 percent
Mean annual precipitation: 1499 to 1670 mm (59 to 66 in)
Precipitation Pattern: Precipitation is generally uniform with slight peaks during the spring and fall months.
Mean annual air temperature: 19.3 to 22 degrees C (67 to 72 degrees F)
Frost-free period: 245 to 304 days
Elevation: 2 to 24 m (6.6 to 79 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Crowley (LA), Edgerly (LA), Judice (LA), Kaplan (LA), Midland (LA), and Vidrine (LA) series.
Crowley and Kaplan soils: are on slightly higher convex shaped surfaces surrounding Mowata soils; do not have a glossic horizon; have red masses of iron accumulation in the subsoil.
Edgerly soils: have a mollic epipedon; are on a slightly higher landform
Judice and Midland soils: are on a similar landform; do not have a glossic horizon; are clayey throughout.
Vidrine soils: are on circular convex mounds; have chroma of 3 or more in the upper subsoil.

DRAINAGE AND PERMEABILITY: Poorly drained. Runoff is negligible. Very slow permeability. A water table is at a depth of 0 to 2 feet below the surface during the months of December through April. Rare to occasional flooding.

USE AND VEGETATION: Native vegetation was tall prairie grasses. Most of the soils are used for rice, soybeans, and grain sorghum, rotated with crayfish aquaculture and pasture.

DISTRIBUTION AND EXTENT: Southwest Louisiana and southeast Texas (MLRA 150A, LRR T). The series is of large extent.

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

SERIES ESTABLISHED: Evangeline Parish, Louisiana; 1970.

REMARKS: This soil was formerly included in the Midland series.
Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon--from a depth of 0 to 36 cm (0 to 14 in) (Ap and Eg horizons).
Albic horizon--from a depth of 13 to 36 cm (5 to 14 in) (Eg horizon).
Argillic horizon--from a depth of 36 to 130 cm (14 to 51 in) (Btg/Eg, Btgl, Btg2, and Btg3 horizons).
Glossic horizon--from a depth of 36 to 56 cm (14 to 22 in) (Btg/E horizon).
Slickensides--at a depth of 130 to 229 cm (51 to 90 in) (Btssg and Ckssg horizons).
Aquic moisture regime.

ADDITIONAL DATA: Laboratory data on the typifying pedon from Louisiana Agriculture Experiment Station, sample number S96LA-001-1.

Taxonomic Version: Keys to Soil Taxonomy, Eleventh Edition, 2010.


National Cooperative Soil Survey
U.S.A.