LOCATION WRIGHTSVILLE AR+LA OK TXEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, thermic Typic Glossaqualfs
TYPICAL PEDON: Wrightsville silt loam, in woodland. (Colors are for moist soil unless otherwise stated.)
Oi--0 to 1 inches; black (10YR 2/1) partially decomposed leaves, twigs, and roots; extremely acid.
A--1 to 2 inches; dark grayish brown (10YR 4/2) silt loam; weak fine granular structure; friable; many medium roots; extremely acid; abrupt smooth boundary. (0 to 5 inches thick)
Eg1--2 to 10 inches; grayish brown (10YR 5/2) silt loam; weak medium granular structure; friable; many medium roots; extremely acid; abrupt smooth boundary. (8 to 14 inches thick)
Eg2--10 to 17 inches; gray (10YR 6/1) silt loam; weak medium subangular blocky structure; friable; many medium and fine roots; common fine pores; common medium distinct yellowish brown (10YR 5/8) masses of iron accumulation in matrix; extremely acid; clear wavy boundary. (5 to 12 inches thick)
Btg/E--17 to 23 inches; (Btg) gray (10YR 5/1) silty clay loam; weak medium prismatic structure parting to weak medium subangular blocky; firm; common continuous distinct clay films on faces of peds; (E) about 20 percent of matrix consists of intrusions of albic material 0.5 to 2 inches wide that is light gray (10YR 7/1) silt loam; massive; friable; common fine roots mainly in Eg material; few fine pores mainly in Eg material; common medium distinct yellowish brown (10YR 5/6) masses of iron accumulation throughout; light gray (10YR 7/2) clay depletions on faces of prisms; extremely acid; gradual wavy boundary. (4 to 12 inches thick)
Btg1--23 to 39 inches; gray (10YR 5/1) silty clay; weak medium prismatic structure parting to strong medium subangular blocky; firm; few fine roots; few fine pores; continuous distinct clay films on faces of peds; about 10 percent of matrix composed of tongues 0.5 to 1 inch wide , interfingers and small pockets of light gray (10YR 7/2) silt loam clay depletions; light gray (10YR 7/2) clay depletions on prism faces; common medium distinct strong brown (7.5YR 5/6) masses of iron accumulation in matrix; extremely acid; gradual smooth boundary. (5 to 18 inches thick)
Btg2--39 to 49 inches; light brownish gray (2.5Y 6/2) silty clay loam; weak medium prismatic structure parting to strong medium subangular blocky; firm; few fine roots; many patchy distinct clay films on faces of peds; small pockets of light gray (10YR 7/2) silt loam clay depletions in matrix and on prism faces; many medium distinct strong brown (7.5YR 5/8) masses of iron accumulation in matrix; extremely acid; gradual smooth boundary. (8 to 13 inches thick)
Btg3--49 to 62 inches; light brownish gray (2.5Y 6/2) silt loam; weak coarse prismatic structure parting to moderate medium subangular blocky; firm; few fine roots; common patchy distinct clay films on faces of peds; common medium distinct strong brown (7.5YR 5/8) masses of iron accumulation in matrix; few small dark brown iron-manganese concretions; light gray (10YR 7/2) clay depletions on prism faces and in small pockets in matrix; extremely acid; clear smooth boundary. (10 to 15 inches thick)
Btg4--62 to 72 inches; gray (10YR 5/1) silt loam; moderate medium angular blocky structure; firm; few fine roots; few patchy distinct clay films on faces of peds; light gray (10YR 7/2) silt clay depletions in small pockets in matrix; common coarse prominent strong brown (7.5YR 5/8) masses of iron accumulation in matrix; extremely acid.
TYPE LOCATION: Conway County, Arkansas; about 5 miles northwest of Oppelo on Highway 154 and 0.5 mile west on county road in SW1/4NE1/4SW1/4 sec. 6, T. 5 N., R. 17 W.
RANGE IN CHARACTERISTICS:
Solum thickness: 40 to more than 72 inches
Clay content in the Control Section: 35 to 55 percent
Redoximorphic features: Depleted matrix with iron concentrations in shades of brown and yellow throughout the solum.
Other distinctive soil features: None
Concentrated minerals: None
A or Ap horizon:
Color--Hue 10YR, value 3 to 5, and chroma of 2. The Ap horizon, when present, has hue of 10YR, value of 4 or 5, and chroma of 2.
Redoximorphic features--None
Texture--Silt, silt loam or silty clay loam
Other features--None
Reaction--Extremely acid to strongly acid
E horizon:
Color--Hue of 10YR, value of 5 to 7, and chroma of 1 or 2, or with hue of 2.5Y, value of 6 or 7, and chroma of 2
Redoximorphic features--Iron accumulation and depletions are in shades of brown and gray
Texture--Silt or silt loam
Other features--None
Reaction--Extremely acid to strongly acid
Btg/E horizon:
Color--Hue of 10YR, value of 4 to 7, and chroma of 1 or 2, or with hue of 2.5Y, value of 5 to 7, and chroma of 2 in the Btg parts; and hue of 10YR, value of 5 to 7, and chroma of 1 or 2, or with hue of 2.5Y, value of 6 or 7, and chroma of 2 in the E parts
Redoximorphic features--Iron accumulation and depletions are in shades of brown, yellow, and gray
Texture--Silty clay, clay, and silty clay loam in the Btg parts; and silt or silt loam in the E parts
Other features--None
Reaction--Extremely acid to moderately acid
Upper part of the Btg horizon:
Color--Hue of 10YR, value of 4 to 7, and chroma of 1 or 2, or with hue of 2.5Y, value of 5 to 7, and chroma of 2
Redoximorphic features--Iron accumulation are in shades of brown or yellow
Texture--Silty clay, clay, clay loam, and silty clay loam
Other features--None
Reaction--Extremely acid to moderately acid
Lower part of the Btg horizon:
Color--Hue of 10YR, value of 4 to 7, and chroma of 1 or 2, or with hue of 2.5Y, value of 5 to 7, and chroma of 2
Redoximorphic features--Iron accumulation are in shades of brown or yellow
Texture--Silt loam, silty clay loam, silty clay, clay, and clay loam
Other features--None
Reaction--Extremely acid to moderately alkaline
C horizon: (where present)
Color--Hue of 10YR, value of 4 to 7, and chroma of 1 or 2, or with hue of 2.5Y, value of 5 to 7, and chroma of 2
Redoximorphic features--Iron accumulation are in shades of brown or yellow
Texture--Silt loam, silty clay loam, silty clay
Other features--None
Reaction--Extremely acid to moderately alkaline
2C horizon: (where present)
Color--Reddish hue
Redoximorphic features--Iron accumulation are in shades of brown or yellow
Texture--Clay or silty clay
Other features--None
Reaction--Neutral to moderately alkaline
COMPETING SERIES: There are no other series in the same family.
GEOGRAPHIC SETTING: Wrightsville soils are on level areas in depressions on old stream terraces. Slopes are less than one percent. This soil formed in old silty and clayey alluvium. Mean annual temperature ranges from 60 degrees to 65 degrees F., and the mean annual precipitation ranges from 44 to 52 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Acadia, Elysian, Foley, Lafe, McKamie, and Muskogee series. Acadia soils are somewhat poorly drained and on slightly higher stream terraces. Elysian soils are moderately well drained, have less clay in the control section and are on circular mounds on terraces. Foley and Lafe soils have a natric horizon and are on lower sideslope positions on terraces. The well drained McKamie soils and moderately well drained Muskogee soils are on higher terraces. Acadia, McKamie, and Muskogee soils do not have aquic conditions within a depth of 20 inches, and do not have a depleted matrix within the upper 5 inches of the argillic horizon.
DRAINAGE AND PERMEABILITY: Wrightsville soils are poorly drained. Runoff is slow and permeability is very slow. The soil is wet in the layers below a depth of 0.5 to 1.5 feet and above the Btg horizon during December through April in normal years.
USE AND VEGETATION: Most of these soils are in forest or pasture. Some areas are used for rice, soybeans, and cotton. Native trees are sweetgum, water oak, and willow oak.
DISTRIBUTION AND EXTENT: Arkansas, Louisiana, Oklahoma, and Texas. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Little Rock, Arkansas
SERIES ESTABLISHED: Pulaski County, Arkansas; 1922.
REMARKS: The series was updated in 2004 to allow clay loam texture in the Btg horizon, and for clay texture to continue into the lower parts of the Btg horizon. Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon-Surface to a depth of 17 inches (A, Eg1 & Eg2 horizons).
Albic horizon-1 to 17 inches (Eg1 & Eg2 horizons).
Glossic horizon-17 to 23 inches (Btg & Eg horizon)
Argillic horizon-17 to 72 inches (Btg & Eg, Btg1, Btg2, Btg3, Btg4 horizons)