LOCATION BUXIN LAEstablished Series
TYPICAL PEDON: Buxin clay - artificially drained hayfield. (Colors are for moist soil unless otherwise stated.)
A--0 to 2 inches; dark reddish brown (5YR 3/3), interior, and dark reddish brown (5YR 3/2), exterior, clay; strong medium angular blocky structure; firm, very sticky and very plastic; many fine roots; common fine pores; common distinct very dark gray (10YR 3/1) organic coats in root channels and pores; slightly acid; clear wavy boundary. (2 to 10 inches thick)
Bw1--2 to 11 inches; dark reddish brown (5YR 3/3), interior, and dark reddish brown (5YR 3/2), exterior, clay; strong medium subangular blocky structure; firm, very sticky and very plastic; many fine roots; common fine pores; common distinct very dark gray (10YR 3/1) organic coats in root channels and pores; few fine dark grayish brown (10YR 4/2) iron depletions throughout; neutral; clear wavy boundary.
Bw2--11 to 20 inches; dark reddish brown (5YR 3/3) clay; strong medium angular blocky structure; firm, very sticky and very plastic; many fine roots; few fine pores; common distinct pressure faces on faces of peds; few medium very dark gray (2.5Y 3/1) iron depletions between peds; common medium yellowish red (5YR 4/6) masses of iron accumulation between peds; moderately alkaline; clear wavy boundary.
Bw3--20 to 28 inches; dark reddish brown (5YR 3/3) clay; strong medium angular blocky structure; firm, very sticky and very plastic; common fine roots; few fine pores; common distinct pressure faces on faces of peds; common medium dark gray (7.5YR 4/1) iron depletions between peds; moderately alkaline; abrupt wavy boundary. (10 to 30 inches thick)
2Ab--28 to 33 inches; dark gray (7.5YR 4/1) silty clay; moderate medium angular blocky structure parting to wedge-shaped aggregates; firm, very sticky and very plastic; common fine roots; common fine pores; thin (1 inch) layer of gray (2.5Y 5/1) clay is at top of horizon; common distinct pressure faces on faces of peds; common fine reddish brown (5YR 4/3) masses of iron accumulation throughout; neutral; clear wavy boundary. (2 to 15 inches thick)
2Bssb1--33 to 50 inches; 60 percent dark gray (5YR 4/1) and 40 percent reddish brown (5YR 4/4) clay; strong medium angular blocky structure parting to wedge-shaped aggregates; firm, very sticky and very plastic; common fine roots; few fine pores; few fine strong brown (7.5YR 5/6) loamy lenses; common distinct intersecting slickensides and common distinct pressure faces on faces of peds; common medium reddish brown (5YR 4/3) masses of iron accumulation between peds; common medium brown (10YR 5/3) masses of iron accumulation between peds; common fine dark gray (5YR 4/1) iron depletions between peds; slightly alkaline; clear wavy boundary.
2Bssb2--50 to 59 inches; brown (7.5YR 4/3) clay; strong medium angular blocky structure parting to wedge-shaped aggregates; firm, very sticky and very plastic; few fine roots; few fine pores; common distinct intersecting slickensides and common distinct pressure faces on faces of peds; many fine strong brown (7.5YR 4/6) masses of iron accumulation between peds; common medium gray (7.5YR 5/1) iron depletions between peds; few fine strong brown (7.5YR 5/6) masses of iron accumulation between peds; common fine very dark gray (10YR 3/1) masses of iron-manganese accumulation throughout; slightly alkaline; clear wavy boundary. (10 to 40 inches thick)
2Bkb--59 to 67 inches; reddish brown (5YR 4/4) sandy clay loam; strong medium subangular blocky structure; friable, slightly sticky and slightly plastic; few fine roots; many fine pores; few faint clay films on faces of peds; many medium gray (5YR 6/1) iron depletions between peds; many medium reddish gray (5YR 5/2) iron depletions between peds; many coarse yellowish brown (10YR 5/8) carbonate nodules throughout; strongly effervescent on nodules (HCl, 1 normal); strongly alkaline; abrupt wavy boundary. (0 to 20 inches thick)
2BCkb--67 to 78 inches; reddish brown (5YR 4/4) very fine sandy loam; weak medium subangular blocky structure; very friable; few fine roots; common fine pores; very few faint clay films; common fine strong brown (7.5YR 4/6) masses of iron accumulation throughout; common fine pinkish gray (7.5YR 6/2) iron depletions between peds; common coarse carbonate nodules throughout; strongly effervescent on nodules (HCl, 1 normal); moderately alkaline; clear wavy boundary. (0 to 20 inches thick)
2Cb--78 to 108 inches; strong brown (7.5YR 4/6) very fine sandy loam; weak coarse subangular blocky structure; very friable; few fine pores; common fine strong brown (7.5YR 5/8) masses of iron accumulation throughout; common fine brown (7.5YR 5/3) iron depletions throughout; moderately alkaline.
TYPE LOCATION: Bossier Parish, Louisiana, about 5.7 miles southeast of Benton, La.; 1.45 miles east of the intersection of U.S. Hwy. 80 and Swan Lake Road on U.S. Hwy. 80; then 174 feet north of the center of the west bound lane of Hwy. 80 into a hayfield; 32 degrees 32 minutes 31.8 seconds N. Latitude, 93 degrees 38 minutes 50.0 seconds W. Longitude; USGS Bossier City USGS 7.5 Minute Quadrangle
RANGE IN CHARACTERISTICS: Solum thickness, including buried A and B horizons, ranges from 60 to more than 80 inches. Depth to buried horizons ranges from 20 to 36 inches; depth to calcareous subhorizons or carbonate nodules is 40 to 60 inches or more.
The Ap or A horizon has hue of 2.5YR to 7.5YR, value of 2 or 3, and chroma of 2 to 4. Texture is clay, silty clay, or silty clay loam. Reaction ranges from slightly acid to slightly alkaline.
The Bw horizon to a depth of 12 inches or more has the same color range as the A horizon. Below 12 inches the B horizon has hue of 5YR or 2.5YR, value of 3 or 4, and chroma of 2 to 4. Few to common iron depletions in shades of gray and iron accumulations in shades of brown or red are in the Bw horizon in some pedons. Texture is clay with average clay content greater than 60 percent. The Bw horizon is noncalcareous and does not contain masses or nodules of free lime. Reaction ranges from slightly acid to moderately alkaline.
The 2Ab horizon has hue of 5YR to 10YR, value of 3 or 4, and chroma of 1 or 2, with or without iron accumulations in shades of red or brown. Texture is clay or silty clay. Reaction ranges from slightly acid to slightly alkaline.
The 2Bssb horizon has hue of 5YR to 7.5YR, value of 3 or 4, and chroma of 1 to 4. Iron depletions in shades of gray and iron accumulations in shades of brown or red range from few to common. Texture is clay. Reaction is slightly acid to slightly alkaline.
The 2Bkb horizon, where present has hue of 5YR to 7.5YR, value of 3 or 4, and chroma of 1 to 4. Iron depletions in shades of gray and iron accumulations in shades of brown or red range from few to common. Texture is clay, silty clay, clay loam or sandy clay loam. Nodules or soft masses of calcium carbonate range from few to many. Reaction ranges from neutral to strongly alkaline.
A 2BC or 2C horizon is below a depth of 60 inches in some pedons. The 2BC or 2C horizon has hue of 5YR or 7.5YR, value of 4 or 5, and chroma of 2 to 6. Texture ranges from very fine sandy loam to clay. Reaction ranges from neutral to moderately alkaline, and the layers are calcareous in some pedons.
COMPETING SERIES: These are the Lebeau and Texark series. Lebeau soils have a dark surface layer that is 8 inches or less in thickness. Texark soils formed in more yellowish alluvium from streams that drain the Blackland Prairies.
GEOGRAPHIC SETTING: Buxin soils are on nearly level to depressed bottomlands of the Red and Arkansas Rivers. These soils formed in clayey alluvium derived chiefly from Permian red beds. The climate is warm and humid; the annual Thornthwaite P-E index is greater than 64. Mean annual precipitation ranges from 38 to 58 inches. The mean annual temperature ranges from 57 to 70 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Lebeau series, and the Billyhaw, Caspiana, Coushatta, Desha, Gallion, Latanier, Moreland, Norwood, Perry, Portland, and Roebuck series. Billyhaw soils are not saturated within a depth of 40 inches for more than one month in normal years. Caspiana, Coushatta, Gallion, and Norwood soils are coarser textured and do not have grayish mottles within a depth of 30 inches. They are on higher landscape positions. Desha and Portland soils do not have intersecting slickensides within a depth of 40 inches. Latanier soils have a loamy discontinuity within a depth of 40 inches. Moreland soils do not have a buried A horizon within a depth of 40 inches and are on slightly higher landscape positions. Perry soils are grayer and are more strongly acid. They are on lower landscape positions. Roebuck soils are wetter and are on slightly lower landscape positions.
DRAINAGE AND PERMEABILITY: Poorly drained; Buxin soils are saturated in the Ap horizon for more than 30 cumulative days during December through April. They are moist in the layers below that. Most areas have been artificially drained. Rate of runoff is high on slopes less than 1 percent, and very high on slopes of 1 percent or more. Permeability is very slow. Unprotected areas are subject to rare to frequent flooding.
USE AND VEGETATION: The original vegetation was hardwoods. The soil is mostly cleared and used for pasture and to a lesser extent for field crops.
DISTRIBUTION AND EXTENT: Eastern Oklahoma, eastern Texas, Arkansas, and Louisiana. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Little Rock, Arkansas
SERIES ESTABLISHED: Concordia Parish, Louisiana; 1910.
REMARKS: Buxin soils were formerly classified in the Alluvial great soil group. They were reclassified as Vertisols in 1996. The series was updated in 2004 to allow moderately alkaline reaction in the Bw horizon, and strongly alkaline reaction in the 2Bkb horizon. Diagnostic horizons andf features recognized in the type location pedon include:
Ochric epipedon ---------- 0 to 2 inches (Ap horizon)
Cambic horizon ----------- 2 to 78 inches (Bw, 2Bss, 2Bk, and 2BCk horizons)
Slickensides ------------- 33 to 59 inches (2Bss horizons)
Secondary carbonates ----- 59 to 78 inches (2Bk and 2BCk horizons)
Lithologic discontinuity - 28 inches (top of 2Ab horizon)
ADDITIONAL DATA: Characterization by NSSL, Lincoln, Neb.; Sample no. S96LA-015-23