LOCATION CREVASSE MS+AR KY LA MO TN

Established Series
WMM:WMK:RBH; Rev.JDS
10/2018

CREVASSE SERIES

The Crevasse series consists of very deep, excessively drained, rapidly permeable soils that formed in sandy alluvium. These level to gently sloping soils are on splays and recent, sparsely vegetated point bar deposits on the flood plain of the Mississippi River and tributaries; MLRA 131. Slopes range from 0 to 5 percent.

TAXONOMIC CLASS: Mixed, thermic Typic Udipsamments

TYPICAL PEDON: Crevasse sand on a 2 percent slope in a pasture field. (Colors are for moist soil unless otherwise stated.)

A--0 to 4 inches; dark grayish brown (10YR 4/2) sand; single grained; loose; few fine roots; neutral; abrupt smooth boundary. (4 to 10 inches thick)

C1--4 to 20 inches; grayish brown (10YR 5/2) sand; single grained; loose; few fine roots; neutral; gradual smooth boundary.

C2--20 to 60 inches; dark grayish brown (10YR 4/2) sand; single grained; loose; neutral.

TYPE LOCATION: Adams County, Mississippi; Jackson Point in southwestern part of the county, about 3500 feet west of private airplane landing field on field road and 75 feet north of U. S. Engineers Bench Mark and 280 feet west, T. 3 N., R. 5 W., no section.

RANGE IN CHARACTERISTICS: Reaction ranges from moderately acid to moderately alkaline. Some pedons are calcareous.

The A horizon has hue of 10YR, value of 4 to 7, and chroma of 2 to 6. Some pedons have a thin A horizon in hue of 10YR, value of 3, and chroma of 1 or 2. Texture of the A horizon is sand, fine sand, loamy sand, loamy fine sand, silt loam, loam, fine sandy loam, or sandy loam.

The C horizon has hue of 10YR, value of 4 to 6, and chroma of 2 to 6, or hue of 2.5Y, value of 4 or 5, and chroma of 2. Some pedons have hue of 2.5Y, value of 4 or 5, and chroma of 3 that is due to the color of the uncoated sand grains in the lower part of the C horizon. Texture is sand, fine sand, loamy fine sand, or loamy sand. Some pedons have loamy lenses or thin layers of very fine sandy loam or silt loam below a depth of 40 inches.

COMPETING SERIES: These are the Assateague, Buncombe, Malden and Tarboro series in the same family. Assateague soils formed in sandy, beach deposits along the Atlantic sea coast. Buncombe soils formed in sediments from igneous and metamorphic rocks and contain mica. Malden and Tarboro soils have a B horizon with soil structure.

GEOGRAPHIC SETTING: Crevasse soils are on the flood plain of the Mississippi River and tributaries. These level to gently sloping soils formed in sandy, splays mainly along levee breaks and recently deposited sediments on point bars along the main channel of the Mississippi River and tributaries. Slopes range from 0 to 5 percent. The climate is warm and humid. Near the type location, the mean annual temperature is 67 degrees F. and the mean annual precipitation is 56 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beulah, Bruno, Commerce, and Robinsonville series and Riverwash. The somewhat excessively drained Beulah and well drained Robinsonville soils are on the lower slopes of natural levees and on level to undulating flood plain treads. They are in coarse-loamy families. Bruno soils are in natural levee positions and contain strata of finer sediments. The somewhat poorly drained Commerce soils are on flood plain treads lower in the landscape and are in a fine-silty family. Riverwash is the unvegetated sand bars in the main channel of the river.

DRAINAGE AND PERMEABILITY: Excessively drained; negligible rate of runoff; rapid permeability. These soils are typically flooded when in the point bar positions and protected in levee breech positions. The water table typically fluctuates between a depth of 3.5 to 6 feet in the wet season during winter and early in spring, however it is also strongly influenced by river levels and will be higher when the river level is up.

USE AND VEGETATION: Most areas that are protected from flooding are cleared and used for growing pasture and hay. Natural vegetation is cottonwood, elm, hackberry, pecan, sycamore, and willow.

DISTRIBUTION AND EXTENT: Flood plain of the Mississippi River and tributaries in Arkansas, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama

SERIES ESTABLISHED: Tunica County, Mississippi; 1949.

REMARKS: The series was updated in 2004 to allow thin loamy lenses, and chroma 3 sand grains below the control section. Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - the zone from the surface of the soil to a depth of approximately 4 inches (A horizon).

National Cooperative Soil Survey
U.S.A.