LOCATION LAGRUE AREstablished Series
The Lagrue series consists of very deep, poorly drained, very slowly permeable, level soils that formed in clayey alluvium. These soils are in depressions and old abandoned channels on Prairie terraces in Arkansas, MLRA 131. Slopes range from 0 to 1 percent.
TAXONOMIC CLASS: Fine, smectitic, thermic Typic Epiaqualfs
TYPICAL PEDON: Lagrue silty clay loam-cultivated. (Colors are for moist soils unless otherwise stated)
Ap--0 to 4 inches; dark grayish brown (10YR 4/2) silty clay loam; weak medium granular structure; friable; common fine and medium pores; common fine roots; common fine distinct strong brown (7.5YR 5/6) and (7.5YR 5/8) iron concentrations in matrix; common fine iron-manganese concretions; strongly acid; abrupt smooth boundary. (4 to 8 inches thick)
Btg1--4 to 11 inches; gray (10YR 5/1) silty clay loam; moderate medium subangular blocky structure; firm; common fine pores; few fine roots; many prominent clay films on faces of peds and lining pores; common medium distinct strong brown (7.5YR 5/6) and (7.5YR 5/8) iron concentrations in matrix and lining some pores; common fine iron-manganese concretions; common fine black (10YR 2/1) soft manganese masses in matrix; strongly acid; clear smooth boundary.
Btg2--11 to 30 inches; gray (10YR 6/1) silty clay; moderate medium subangular blocky structure; firm; few fine pores; few fine roots; many prominent clay films on faces of peds and lining pores; common medium prominent yellowish red (5YR 5/8) and common medium distinct strong brown (7.5YR 5/8) iron concentrations in matrix; common fine iron-manganese concretions; common fine black (10YR 2/1) soft manganese masses in matrix; extremely acid; clear smooth boundary.
Btg3--30 to 63 inches; light brownish gray (2.5Y 6/2) silty clay; moderate medium subangular blocky structure; firm; common fine pores; few fine roots; many prominent clay films on faces of peds and lining pores; common medium prominent yellowish red (5YR 5/8) and common medium distinct strong brown (7.5YR 5/8) iron concentrations in matrix; common medium distinct gray (10YR 6/1) iron depletions; common fine and medium iron-manganese concretions; common fine black (10YR 2/1) soft manganese masses in matrix; extremely acid; gradual smooth boundary.
Btg4--63 to 80 inches; grayish brown (2.5Y 5/2) silty clay; moderate medium subangular blocky structure; firm; few fine pores; many prominent clay films on faces of peds and lining pores; common medium distinct brown (10YR 5/3) and common medium distinct strong brown (7.5YR 5/8) iron concentrations in matrix; common medium distinct gray (10YR 6/1) iron depletions; common fine and medium iron-manganese concretions; common fine black (10YR 2/1) soft manganese masses in matrix; very strongly acid. (Combined thickness of the Btg horizons is more than 52 inches)
TYPE LOCATION: Arkansas County, Arkansas; approximately 2 miles east of the city of Stuttgart in the NE1/4 NE1/4 NW1/4, sec. 26 T. 2 S., R. 5 W.
RANGE IN CHARACTERISTICS: Solum thickness is more than 60 inches. Sodium saturation ranges up to 10 percent in the lower part of the argillic.
The A or Ap horizon has hue of 10YR, value of 4 or 5, and chroma of 1 or 2. Texture is silt loam or silty clay loam. Iron accumulations and depletions are in shades of yellow, brown, or gray. Reaction ranges from strongly acid to neutral.
The Btg horizons have hue of 5Y, 2.5Y, or 10YR, value of 4 to 6, and chroma of 1 or 2. Texture is silty clay loam, silty clay, or clay. Average clay content ranges from 40 to 60 percent to a depth of 40 inches and from 35 to 60 percent below 40 inches. Iron accumulations and depletions are in shades of red, brown, or gray. Reaction ranges from extremely acid to moderately acid.
COMPETING SERIES: There are no other series in this family. Soils in closely related families include the Acadia, Ivanhoe, and Tensas series in an aeric subgroup, and the Natalbany and Panola series in a vertic subgroup.
GEOGRAPHIC SETTING: Lagrue soils are on level to slightly concave areas on Pleistocene Prairie terraces. These areas are thought to be old abandoned river channels and courses. The parent material is mainly aluvium, but some areas may have been mixed with loess. Slopes range from 0 to 1 percent. Lagrue soils formed in clayey sediments deposited by the Mississippi River and its tributaries. Climate is warm and humid. Mean annual temperature ranges from about 62 to 66 degrees F. Average annual precipitation ranges from about 50 to 55 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dewitt and Stuttgart series. Dewitt and Stuttgart soils occur on adjacent higher landscapes, and have abrupt texture changes between the ochric epipedon and the argillic horizon. Stuttgart soils are in a udic moisture regime.
DRAINAGE AND PERMEABILITY: Poorly drained; negligible or low surface runoff; very slow permeability. These soils are saturated in the surface and upper subsoil horizons during the winter and early spring in most years.
USE AND VEGETATION: Most areas have been cleared and used for the production of rice and soybeans. Small, scattered, wooded tracts of native, bottomland hardwoods remain in some areas.
DISTRIBUTION AND EXTENT: MLRA 131; Grand Prairie of Arkansas and possibly other Pleistocene terraces in Louisiana. Lagrue soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Arkansas County, Arkansas; 2001
REMARKS: Lagrue soils were formerly included in the Midland series. Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon-0 to 4 inches (Ap)
Aquic conditions-0 to 11 inches (Ap and Btg1)
Episaturation-0 to 11 inches (AP and Btg1)
Argillic horizon-4 to 80 inches (Btg1, Btg2, Btg3, and Btg4)
ADDITIONAL DATA: Characterization of the typical pedon was done by the University of Arkansas Soil Characterization Laboratory. Pedon 93AR04.