LOCATION MCLAURIN MS+AL AR LA VAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, siliceous, subactive, thermic Typic Paleudults
TYPICAL PEDON: McLaurin loamy sand--forested.
(Colors are for moist soil unless otherwise stated.)
A--0 to 5 inches; very dark grayish brown (10YR 3/2) loamy sand; weak fine and medium granular structure; very friable; strongly acid; clear smooth boundary. (3 to 9 inches thick)
E--5 to 8 inches; dark grayish brown (10YR 4/2) loamy sand; weak fine and medium granular structure; very friable; strongly acid; clear wavy boundary. (0 to 5 inches thick)
EB--8 to 14 inches; yellowish brown (10YR 5/4) sandy loam; weak fine granular structure; very friable; mixing in upper part by earthworm action; strongly acid; gradual wavy boundary. (0 to 10 inches thick)
Btl--14 to 20 inches; yellowish red (5YR 5/6) fine sandy loam; weak fine and medium subangular blocky structure; very friable; clay bridging of sand grains and few thin clay films on faces of peds; strongly acid; gradual wavy boundary.
Bt2--20 to 32 inches; yellowish red (5YR 4/6) fine sandy loam; weak medium to coarse subangular blocky structure; friable; clay bridging of sand grains and few thin clay films on faces of peds; strongly acid; diffuse wavy boundary.
Bt3--32 to 38 inches; yellowish red (5YR 4/6) sandy loam; weak coarse subangular blocky structure; very friable; clay bridging of sand grains; strongly acid; diffuse wavy boundary. (Combined thickness of the Bt subhorizons is 18 to 40 inches.)
B/E--38 to 49 inches; yellowish red (5YR 4/8) loamy fine sand (B); with coarse subangular blocky structure; very friable; common fine roots; common fine pores; many fine reddish yellow (7.5YR 6/6) pockets of uncoated sand grains (E); very strongly acid; diffuse irregular boundary. (6 to 12 inches thick)
B't--49 to 60 inches; red (2.5YR 4/6) sandy clay loam, weak coarse subangular blocky structure; friable; sand grains coated and bridged with clay; very strongly acid.
TYPE LOCATION: Forrest County, Mississippi; 2 miles west of McLaurin, 0.9 mile north of Lake Shelby, and 300 feet west of U. S. Highway 49.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 inches to more than 80 inches. In some pedons a few ironstone fragments or chert gravel, or both make up less than 10 percent of the volume are present in some pedons. Reaction is strongly acid to very strongly acid throughout, except where the surface layers have been limed.
The A or Ap horizon has hue of 10YR, value of 3 to 5 and chroma of 2 or 3, or hue of 10YR, value of 4, and chroma of 4; or hue of 10YR, value of 5, and chroma of 4 to 6, or hue of 7.5YR, value of 5, and chroma of 4; however, a value of 3 with chroma of 2 or less is limited to horizons with a thickness of less than 6 inches. The texture range is sandy loam, fine sandy loam, loamy sand, or loamy fine sand.
The E horizon, where present, has hue of 10YR, value of 4 to 6, and chroma of 2 to 6 or hue of 7.5YR, value of 5, and chroma of 4. It is sandy loam, fine sandy loam, loamy sand, or loamy fine sand.
The EB horizon, where present, has hue of 10YR, value of 4 to 6, and chroma of 4 to 8, or hue of 7.5YR, value of 5, and chroma of 6. It is sandy loam, fine sandy loam, loamy sand, or loamy fine sand.
The Bt horizon has hue of 5YR to 10R, value of 4 or 5, and chroma of 4 to 8. It is loam, sandy loam, or fine sandy loam. The particle size control section, the upper 20 inches of the Bt horizon, has 10 to 18 percent clay and 20 to 50 percent silt.
The B part of the B/E horizon has the same range in color as the Bt horizon. It is loamy sand, sandy loam, or fine sandy loam. The E part of the material is almost stripped of clay. It has hue of 7.5YR or 10YR, value of 6 to 8, and chroma of 3 to 8, and makes up about 10 to 25 percent of the volume in a discontinuous pattern. Some pedons have an E/B horizon.
The B't horizon has hue of 5YR to 10R, with value of 4 or 5, and chroma of 4 to 8. It is sandy clay loam, sandy loam, or loam.
COMPETING SERIES: These are the Benndale, Butters, Heidel, and Niwana series in the same family and the closely related Bassfield, Brogdon, Cahaba, Lucy, Ora, Ruston, Smithdale, and Troup soils. Benndale and Niwana soils have a Bt horizon with hue of 7.5YR or yellower. Butters soils do not have as much as 20 percent silt in the top 20 inches of the Bt horizon. Heidel soils do not have a bisequum. The Bassfield soils have a solum 40 to 60 inches thick. Brogdon soils have less than 20 percent silt in the upper 20 inches of the Bt horizon and more than 5 percent plinthite in the lower part of the subsoil. Cahaba soils have a fine loamy control section and a solum that is less than 60 inches thick. Ruston and Smithdale soils are in a fine loamy family. Lucy and Troup soils have a sandy epipedon more than 20 inches thick. Ora soils have a fragipan.
GEOGRAPHIC SETTING: The McLaurin soils are in nearly level to sloping uplands on slopes ranging from 0 to 8 percent in the Southern Coastal Plain Major Land Resource Area. They commonly are on broad ridgetops and upper hillsides of ridges dividing major streams. The regolith is loamy marine or stream deposits. The climate is warm and humid. The mean annual temperature is 64 degrees Fahrenheit and the mean annual precipitation is 61 inches near the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Heidel, Lucy, Ora, Ruston, Smithdale, and Troup series and the Eustis and Sweatmen series. Well drained Heidel and Smithdale soils mainly are on steeper hillsides than the McLaurin soils. Moderately well drained Ora soils are in slightly higher positions on ridgetops. Well drained Ruston soils are on associated very gently sloping to sloping uplands. Excessively drained Eustis soils, which have a sandy particle-size control section, and the well drained Lucy and Troup soils are in more dissected parts of the landscape. Sweatman soils, which commonly are on lower positions on hillsides, have a clayey particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained; runoff is slow to medium; moderate permeability.
USE AND VEGETATION: Cotton, corn, soybeans, and small grains are the principal crops. Many areas are used for pasture and woodland. Principal vegetation of uncleared areas is longleaf, slash, loblolly, and shortleaf pines, or mixed hardwoods and pines with an understory of shrubs and grasses.
DISTRIBUTION AND EXTENT: Alabama, Arkansas, Louisiana, and Mississippi. The series is of large extent.
MLRA OFFICE RESPONSIBLE: Auburn, Alabama
SERIES ESTABLISHED: Lamar County, Mississippi; 1969.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface to a depth of about 5 inches (A horizon).
Argillic horizon - the zone from approximately 14 to 60 inches (Bt1, Bt2, Bt3, B/E, B't horizons).
ADDITIONAL DATA: Laboratory data: Chemical analyses, particle-size distribution, and engineering test data for the typical pedon are published in the Soil Survey of Forrest County, Mississippi (issued April 1979) pp. 101-102. Chemical analyses and particle-size distribution for one pedon are published in the Soil Survey of Lauderdale County, Mississippi (issued July 1983) pp. 135-136.