Lufkin soil series
Profile of Lufkin loam. Texture and color change between the surface layer and the clay subsoil. (Soil Survey of Robertson County, Texas; By Harold W. Hyde, Natural Resources Conservation Service)
The Lufkin series consists of very deep, moderately well drained, very slowly permeable soils on high terraces or remnants of terraces associated with uplands. The soil formed in slightly acid to alkaline clayey sediments. Slopes are dominantly less than 1 percent but range to 3 percent.
TAXONOMIC CLASS: Fine, smectitic, thermic Oxyaquic Vertic Paleustalfs
Solum thickness ranges from 60 to more than 80 inches. Base saturation ranges from 80 to 100 percent by sum of cations throughout the argillic horizon. Clay content of the 10- to 40- inch particle size control section ranges from 35 to 45 percent. When dry, cracks at least 1/4 inch wide extend from the top of the argillic horizon through a thickness of 12 inches or more within the upper 50 inches of the soil. Slickensides and/or wedge-shaped aggregates and pressure faces range from few to common throughout the argillic horizon. Linear extensibility is greater than 2.5 inches (6.0 cm) in the upper 40 inches (100 cm) of the soil. COLE ranges from 0.07 to 0.10 in the upper 50 inches of the argillic horizon. Siliceous pebbles range from none to 10 percent of some subhorizons. Most pedons contain secondary carbonates, barite masses, or gypsum crystals beginning at a depth of 40 to 70 inches. Redox features are both relict and contemporary. The soil does not have aquic soil conditions in most years.
USE AND VEGETATION: Mostly cultivated in the past but now most areas are in unimproved pastures. Some areas are farmed to grain sorghums, hay crops or small grains for grazing. Other areas are in mixed bermudagrass, dallisgrass, or bahiagrass pastures. Native vegetation is bluestems, gramas, paspalums and threeawn grasses with sedges, post oak, water oak, willow oak, and elm trees.
DISTRIBUTION AND EXTENT: Mainly in the Texas Claypan region of Texas (MLRA 87A, 87B, and to a lesser extent, on terraces of 86A).
Classification change from Udertic Paleustalfs to Oxyaquic Vertic Paleustalfs based on knowledge that these soils are saturated for 2 to 4 weeks in most years. This period of time is within the definition of saturation for one month or more if rules of rounding are applied, i.e., 2 to 6 weeks saturation is considered inclusive. The soil would classify in the Epioxyaquic subgroup if provided for by SOIL TAXONOMY.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/texas/TX395/0/...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/L/LUFKIN.html
For acreage and geographic distribution, visit:
casoilresource.lawr.ucdavis.edu/see/#lufkin
Lufkin soil series
Profile of Lufkin loam. Texture and color change between the surface layer and the clay subsoil. (Soil Survey of Robertson County, Texas; By Harold W. Hyde, Natural Resources Conservation Service)
The Lufkin series consists of very deep, moderately well drained, very slowly permeable soils on high terraces or remnants of terraces associated with uplands. The soil formed in slightly acid to alkaline clayey sediments. Slopes are dominantly less than 1 percent but range to 3 percent.
TAXONOMIC CLASS: Fine, smectitic, thermic Oxyaquic Vertic Paleustalfs
Solum thickness ranges from 60 to more than 80 inches. Base saturation ranges from 80 to 100 percent by sum of cations throughout the argillic horizon. Clay content of the 10- to 40- inch particle size control section ranges from 35 to 45 percent. When dry, cracks at least 1/4 inch wide extend from the top of the argillic horizon through a thickness of 12 inches or more within the upper 50 inches of the soil. Slickensides and/or wedge-shaped aggregates and pressure faces range from few to common throughout the argillic horizon. Linear extensibility is greater than 2.5 inches (6.0 cm) in the upper 40 inches (100 cm) of the soil. COLE ranges from 0.07 to 0.10 in the upper 50 inches of the argillic horizon. Siliceous pebbles range from none to 10 percent of some subhorizons. Most pedons contain secondary carbonates, barite masses, or gypsum crystals beginning at a depth of 40 to 70 inches. Redox features are both relict and contemporary. The soil does not have aquic soil conditions in most years.
USE AND VEGETATION: Mostly cultivated in the past but now most areas are in unimproved pastures. Some areas are farmed to grain sorghums, hay crops or small grains for grazing. Other areas are in mixed bermudagrass, dallisgrass, or bahiagrass pastures. Native vegetation is bluestems, gramas, paspalums and threeawn grasses with sedges, post oak, water oak, willow oak, and elm trees.
DISTRIBUTION AND EXTENT: Mainly in the Texas Claypan region of Texas (MLRA 87A, 87B, and to a lesser extent, on terraces of 86A).
Classification change from Udertic Paleustalfs to Oxyaquic Vertic Paleustalfs based on knowledge that these soils are saturated for 2 to 4 weeks in most years. This period of time is within the definition of saturation for one month or more if rules of rounding are applied, i.e., 2 to 6 weeks saturation is considered inclusive. The soil would classify in the Epioxyaquic subgroup if provided for by SOIL TAXONOMY.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/texas/TX395/0/...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/L/LUFKIN.html
For acreage and geographic distribution, visit:
casoilresource.lawr.ucdavis.edu/see/#lufkin