LOCATION KEITHVILLE LA+TXEstablished Series
TAXONOMIC CLASS: Fine-silty, siliceous, semiactive, thermic Glossaquic Paleudalfs
TYPICAL PEDON: Keithville very fine sandy loam, near the crest of a convex ridge on a 3 percent slope, in pine and hardwood woodland. (Colors are for moist soil unless otherwise stated.)
A--0 to 3 inches; brown (10YR 4/3) very fine sandy loam; weak fine granular structure; very friable; many fine and medium roots; many fine pores; few fine dark brown concretions; medium acid; clear smooth boundary. (2 to 7 inches thick)
E--3 to 9 inches; yellowish brown (10YR 5/4) very fine sandy loam; weak fine granular structure; very friable; common fine roots; many fine pores; few fine brown concretions; medium acid; clear smooth boundary. (0 to 9 inches thick)
Bt1--9 to 16 inches; yellowish red (5YR 5/8) loam; moderate medium subangular blocky structure; friable; common fine roots; common fine pores; common fine dark brown concretions; thin patchy clay films on faces of peds and in pores; strongly acid; clear smooth boundary. (5 to 15 inches thick)
Bt2--16 to 22 inches; yellowish red (5YR 4/6) loam; moderate medium subangular blocky structure; friable; common fine roots; common fine pores; common fine dark brown concretions; thin patchy clay films on faces of peds and in pores; strongly acid; clear wavy boundary. (5 to 15 inches thick)
Bt3--22 to 30 inches; strong brown (7.5YR 5/6) loam; few fine distinct light brownish gray (10YR 6/2) mottles; moderate medium subangular blocky structure; friable; few fine roots; common fine pores; thin patchy clay films on surfaces of peds and in pores; thin light yellowish brown (10YR 6/4) silt coats on vertical faces of some peds; strongly acid; clear wavy boundary. (0 to 10 inches thick)
B/E--30 to 35 inches; strong brown (7.5YR 5/6) loam (Bt) many coarse distinct light yellowish brown (10YR 6/4) and red (2.5YR 4/6) mottles; few fine distinct light brownish gray (10YR 6/2) mottles; light brownish gray (10YR 6/2) silt coats on peds are 2 to 5 mm thick and make up 15 percent of horizon (E); moderate medium subangular blocky structure; friable; few fine roots; many fine pores; many fine and medium brown concretions; thin patchy clay films in pores; strongly acid; abrupt wavy boundary. (4 to 10 inches thick)
2Bt4--35 to 43 inches; gray (10YR 6/1) silty clay; many medium prominent red (2.5YR 4/6) and few medium distinct brownish yellowish (10YR 6/6) mottles; weak very coarse prisms that part to weak medium subangular blocky structure; plastic; common fine roots; thick patchy clay films on faces of peds; few fine black concretions; very strongly acid; gradual wavy boundary. (8 to 30 inches thick)
2Bt5--43 to 70 inches; light brownish gray (2.5Y 6/2) silty clay; common medium distinct yellowish brown (10YR 5/6) mottles; weak medium subangular blocky structure; plastic; few fine roots; black stains in root channels; very strongly acid. (10 to 30 inches thick)
TYPE LOCATION: Caddo Parish, Louisiana, 4.5 miles south of Keithville, Louisiana, 60 yards south of intersection of Keithville-Keatchie and Stonewall Road, 25 yards west of Keithville-Keatchie road; SE1/4NW1/4 sec. 24, T. 15 N., R. 15 W.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to about 100 inches. Depth to the clayey 2Bt horizon ranges from 30 to 40 inches. Except for surface horizons that have been limed, reaction ranges from extremely acid through medium acid throughout the solum.
The A or Ap horizon has hue of 10YR, value that ranges from 3 to 6, and chroma of 2, 3, or 4. The E horizon, where present, has hue of 10YR, value of 5 or 6, and chroma of 3 or 4. The A and E horizons are silt loam, loam, or very fine sandy loam.
The Bt horizon has dominant hue of 5YR or 7.5YR, value of 4 or 5, and chroma of 6 or 8. The Bt3 horizon, where present, may range to 10YR hue, value of 5 or 6, and chroma of 6 or 8. The lower part of the Bt horizon has few or common 1 or 2 chroma mottles. The Bt1 and Bt2 horizons are loam, silt loam, or silty clay loam. Total sand content, which is dominantly very fine sand, ranges from 25 to 40 percent. Texture of the Bt3 horizon is the same as that of the Bt1 and Bt2 horizons and includes clay loam.
The Bt part of the B/E horizon is mottled in hue of 2.5YR through 10YR, value of 3 through 6, and chroma of 3 through 6. It is silt loam, loam, silty clay loam, or clay loam. The E part of the B/E horizon is a grayish coated silt or very fine sand.
The 2Bt horizon is mottled with shades of gray, red, and brown. It is silty clay or clay.
COMPETING SERIES: These are the Abita, Glenmora, and Kolin series in the family and the Evangeline, Freestone, Izagora, Stigler, and Vidrine series. Abita, Evangeline, Freestone, and Glenmora soils lack clayey 2Bt horizons. Freestone soils also have a fine-loamy control section. Izagora soils have a fine-loamy over clayey control section and lack interfingering of albic material in the Bt horizon. Kolin soils have less than 25 percent total sand in the argillic horizon. Stigler soils have 10YR hue throughout the Bt horizon. Vidrine soils have a coarse-silty over clayey control section and grayish wetness mottles in the upper 10 inches of the argillic horizon.
GEOGRAPHIC SETTING: Keithville soils are on nearly level or
gently sloping uplands of the Gulf Coastal Plain. Slopes range
from 1 to 5 percent. The soils formed in loamy and clayey Coastal Plain sediments. The climate is warm and humid; the mean annual precipitation is 45 inches, and the mean annual temperature is 65 degrees F. at the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Guyton, Malbis, Woodtell, and Wrightsville series. Guyton soils are more poorly drained and dominantly gray. Malbis soils have a fine-loamy control section and lack clayey 2Bt horizons. Woodtell and Wrightsville soils have clayey control sections. Additionally, Wrightsville soils are gray throughout the solum.
DRAINAGE AND PERMEABILITY: Keithville soils are moderately well drained; runoff is medium; and permeability is very slow. They
have a perched water table at a depth of 2 to 3 feet for
intermittent periods totaling 2 to 6 weeks during December through April
USE AND VEGETATION: Most of the Keithville soils are used for pasture and urban development. A small area is in mixed hardwood
and pine forest.
DISTRIBUTION AND EXTENT: Louisiana and possibly Arkansas and
Texas. Extent is moderate.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Caddo Parish, Louisiana; 1978.
REMARKS: The Keithville series would formerly have been
classified in the Red-Yellow Podzolic great soil group.