LOCATION FRANCITAS TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, hyperthermic Typic Hapluderts
TYPICAL PEDON: Francitas clay--pasture.
(Colors are for moist soil unless otherwise stated.)
A--0 to 16 inches; black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; moderate fine angular and subangular blocky structure; extremely hard, very firm; many fine roots; common fine pores; slightly sodic; slightly alkaline; gradual wavy boundary. (6 to 20 inches thick)
Bss--16 to 38 inches; very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry; strong fine and medium angular blocky structure; extremely hard, very firm; common fine roots; few fine pores; common prominent slickensides; moderately sodic; very slightly saline; moderately alkaline; gradual wavy boundary. (10 to 24 inches thick)
Bssg1--38 to 59 inches; dark gray (10YR 4/1) clay, gray (10YR 5/1) dry; moderate fine and medium angular blocky structure; very hard, very firm; few fine roots and pores; common prominent slickensides; peds have shiny pressure surfaces; few fine concretions of calcium carbonate; strongly sodic; moderately saline; moderately alkaline; gradual wavy boundary. (10 to 30 inches thick)
Bssg2--59 to 69 inches; pale brown (10YR 6/3) clay, very pale brown (10YR 7/3) dry; weak medium angular blocky structure; very hard, very firm; few fine roots and very fine pores; common prominent slickensides; dark gray coatings on surfaces of peds; common fine calcium carbonate concretions and few thin seams of calcium carbonate; few fine iron-manganese concretions; strongly sodic; strongly saline; strongly effervescent; moderately alkaline; gradual wavy boundary. (10 to 22 inches thick)
BCss--69 to 108 inches; light yellowish brown (10YR 6/4) clay, very pale brown (10YR 7/4) dry; massive; very hard, very firm; few medium distinct gray (10YR 6/1) iron depletions; few faint brownish yellow (10YR 6/6) iron concentrations; few slickensides; few fine concretions and masses of calcium carbonate; strongly sodic; strongly saline; strongly effervescent; moderately alkaline.
TYPE LOCATION: Calhoun County, Texas; from the intersection of Texas Highways 238 and 316 which is about 3 miles south of Port Lavaca; 0.95 mile southeast on Texas Highway 316; 1.1 miles northeast on field road; 80 feet northwest of field road in pasture. This point is about 100 feet SE from break in slope to Bay and 100 feet SW of a large gully.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to more than 80 inches. The average clay content of the 10 to 40 inch particle-size control section ranges from 45 to 60 percent. Slickensides begin at a depth of about 10 to 30 inches. Undisturbed areas have gilgai microrelief with micro-highs 3 to 10 inches higher than the micro-lows. Powdery masses or concretions of calcium carbonate are below a depth of 28 inches in over half the pedon. SAR ranges from 6 to 13 in the A or Ap, 13 to 30 in the Bss horizon, and 13 to 50 in the BC and 2C horizons. Salinity increases with depth and the electrical conductivity of the saturation extract (EC) ranges from 1 to 4 dS/m in the A or Ap, 4 to 12 dS/m in the Bss horizon, 4 to 25 dS/m in the Bgss horizon, and 8 to 25 dS/m in the BC and 2C horizons.
The A or Ap horizon has hue of 10YR or N, value of 2 or 3, and chroma of 1 or less. Some pedons contain a few fine brownish or yellowish iron concentrations. Texture is silty clay loam, clay loam, silty clay, or clay with a clay content exceeding 35 percent. Reaction ranges from slightly acid to moderately alkaline.
The Bss horizon has hue of 10YR, value of 2 to 4, and chroma of 1. Some pedons contain a few fine brownish or yellowish mottles. Texture is clay or silty clay with a clay content ranging from 40 to 60 percent. Reaction ranges from neutral to moderately alkaline.
The Bssg horizon has hue of 10YR or 2.5Y, value of 4 to 7, and chroma of 1 to 3. Mottles in shades of brown or yellow range from none to common. Texture is clay or silty clay. Reaction is slightly alkaline or moderately alkaline.
The BC horizon has hue of 10YR to 5Y, value of 5 to 7, and chroma of 1 to 4. Texture is clay loam, silty clay loam, silty clay, or clay. Concretions or masses of calcium carbonate are in the Bssg and BC horizons of most pedons. Reaction is slightly alkaline or moderately alkaline.
Some pedons have a 2C horizon below 60 inches that has color in shades of red, brown, or gray. Texture is very fine sandy loam, silt loam, or silty clay loam. Reaction ranges from neutral to moderately alkaline.
COMPETING SERIES: These are the Ganado, Laewest, and Lake Charles series in the same family. These soils are not sodic or saline. Other similar soils are the Victine, and Victoria series. Victine and Victoria soils are dry in the moisture control section for longer periods of time.
GEOGRAPHIC SETTING: Francitas soils are on broad, nearly level, low uplands on the coastal plains at elevations less than 15 feet above sea level. Slopes are less than 1 percent. Storm surges cover most areas once every 10 to 20 years with sea water. The soil formed in alkaline, clayey sediments of the Beaumont Formation of Pleistocene age. Mean annual temperature is 70 to 73 degrees F. Mean annual precipitation ranges from 33 to 45 inches. Frost-free days range from 280 to 300. The Thornthwaite P-E indices range from 48 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Laewest series, and the Dacosta, Livia, Narta and Palacios series. Dacosta soils have an argillic horizon. Livia, Narta and Palacios soils have loamy surface horizons and have a natric horizon.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; high runoff; very slow permeability. A perched water table occurs in the A and Bss horizons for periods of 1 to 5 weeks in winter and spring.
USE AND VEGETATION: Used for cropland in the production of rice and grain sorghum and for native range. Native grasses are mainly gulf cordgrass, and species of andropogon and paspalum.
DISTRIBUTION AND EXTENT: In the mid coastal region of the Gulf Coast Prairie (MLRA 150B) of Texas. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Calhoun County, Texas; 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon-0 to 38 inches ( A and Bss horizon).
Slickensides-16 to 108 inches (Bss, Bssg, and BCss horizons).
Addition remarks: These soils would classify as a Halic or Sodic subgroup if provided in Soil Taxonomy.
ADDITIONAL DATA: National Soil Survey Laboratory data from Calhoun County, Texas (S70TX-29-25)(Lab Nos. 70L174-70L179) and (S70TX-29-27) (Lab Nos. 70L180-70L180).
TAXONOMIC VERSION: Soil Taxonomy, Second Edition, 1999.