LOCATION MARIETTA MS+AL AR TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, active, thermic Fluvaquentic Eutrudepts
TYPICAL PEDON: Marietta loam - cultivated.
(Colors are for moist soil unless otherwise stated.)
Ap1--0 to 5 inches; brown (10YR 4/3) loam; weak fine granular structure; very friable; many fine and medium roots; neutral; clear smooth boundary.
Ap2--5 to 10 inches; brown (10YR 4/3) silt loam; weak fine granular structure; friable; common fine roots; few gray and red root stains; neutral; abrupt smooth boundary. (Combined thickness of the A horizon is 4 to 16 inches thick)
Bw1--10 to 15 inches; brown (10YR 4/3) silty clay loam; common fine faint light brownish gray (10YR 6/2) mottles; weak fine subangular blocky structure; friable; slightly sticky, slightly plastic; few fine roots; few fine pieces of charcoal; neutral; clear smooth boundary.
Bw2--15 to 24 inches; brown (10YR 4/3) loam; many medium distinct light brownish gray (10YR 6/2) mottles; weak medium subangular blocky structure; friable, slightly plastic, slightly sticky; few fine roots; few fine brown concretions; neutral; gradual smooth boundary. (Combined thickness of upper part of the Bw horizon is 10 to 20 inches)
Bw3--24 to 46 inches; mottled light brownish gray (2.5Y 6/2) and yellowish brown (10YR 5/8) sandy clay loam; weak medium subangular blocky structure; friable; slightly plastic, slightly sticky; few fine roots; few fine black concretions; slightly acid; diffuse boundary. (10 to 30 inches thick)
Cg--46 to 62 inches; light brownish gray (2.5Y 6/2) sandy clay; many coarse distinct yellowish brown (10YR 5/8) mottles; massive; firm; plastic, sticky; common fine black concretions; slightly acid.
TYPE LOCATION: Lee County, Mississippi; 1 mile southwest of Shannon Post Office, south side of Chiwapa Creek, 116 feet north of TVA power line pole No. 99. NE1/4SW1/4 sec. 24, T. 11 S., R. 5 E.
RANGE IN CHARACTERISTICS: The solum ranges from 28 to 60 inches thick. The reaction ranges from medium acid to mildly alkaline, except the surface layers in areas that have been limed.
The A horizon has hue of 10YR or 2.5Y, value of 4 or 5, and chroma of 2 to 4. Some pedons have a thin A horizon in hue of 10YR, value of 3, and chroma of 2 or 3. Texture is silt loam, very fine sandy loam, loam, or fine sandy loam.
The upper part of the Bw horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 4 or 5, and chroma of 3 or 4; mottles having chroma of 2 or less are within a depth of 24 inches of the surface and commonly increase in size and abundance with depth. The lower part of the Bw horizon commonly is mottled in shades of brown, yellow, and gray; in some pedons, it is gleyed and has a matrix in hue of 10YR or 2.5Y, value of 5 or 6, and chroma of 1 or 2, with mottles in shades of brown, yellow, and gray. Texture is silty clay loam, clay loam, sandy clay loam, loam, or silt loam. The 10- to 40-inch control section has 18 to 30 percent clay. Black concretions are few to many in the lower part of the B horizon.
The C horizon has hue of 10YR or 2.5Y, value of 5 or 6, and chroma of 1 or 2, with mottles in shades of brown, yellow, and gray; or it is mottled in shades of these colors. Texture is silty clay loam, clay loam, sandy clay loam, sandy clay, or silt loam. Fine to coarse black concretions are few to common.
COMPETING SERIES:
Hamblen is the only competing series. Closely related series include the
Belden,
Bruin,
Catalpa,
Commerce,
Leeper,
Lobelville,
Mantachie,
Thenas, and
Whitesburg soils.
Hamblen soils typically have thinner sola with thin fragments of shale or sandstone and pebbles or cobbles of quartzite are throughout. Belden and Commerce soils are fine-silty in the particle-size control section. Bruin soils are coarse-silty in the particle-size control section. Catalpa and Leeper soils are fine in the particle-size control section; also, Catalpa soils have a mollic epipedon, 10- to 24-inches thick. Lobelville soils are strongly acid to medium acid and have chert fragments throughout. Mantachie soils have a grayish matrix within a depth of 20 inches and are very strongly to strongly acid throughout. Thenas soils are coarse-loamy in the particle-size control section and have mixed mineralogy. Whitesburg soils have a mesic temperature class.
GEOGRAPHIC SETTING: These are nearly level soils on wide flood plains of streams that drain areas in the mixed uplands of the Southern Coastal Plain and Blackland Prairie Major Land Resource Areas. Marietta soils formed in loamy alluvium. Slopes range from 0 to 2 percent. The mean annual precipitation is 51 inches and the mean annual temperature is 64 degrees Fahrenheit near the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Catalpa, Leeper and Mantachie soils listed as competing series and the Houlka and Tuscumbia series. These are somewhat poorly drained soils that are across the nearly linear surfaces of floodplains and are in similar positions as the Marietta soils, except the poorly drained Tuscumbia soils, which are in slightly lower areas or backwater sloughs. Houlka and Tuscumbia are fine in the particle-size control section; and in addition, Houlka soils are acid.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow or very slow runoff; and moderate permeability. This soil is subject to occasional or frequent flooding for brief duration. The water table is within a depth of 1.5 to 2.0 feet of the surface during periods of high rainfall.
USE AND VEGETATION: Most areas of this soil are cleared and used for growing cotton, soybeans, corn, and small grains. Some areas are used for growing pasture and hay. The native vegetation is mixed hardwoods, including green ash, eastern cottonwood, sweetgum, American sycamore, and yellow-poplar.
DISTRIBUTION AND EXTENT: Alabama, Arkansas, Mississippi, and Texas. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama
SERIES ESTABLISHED: Prentiss County, Mississippi; 1947.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface to a depth of about 10 inches (Ap1, Ap2 horizons).
Cambic horizon - the zone from approximately 10 to 46 inches (Bw1, Bw2, Bw3 horizons).
ADDITIONAL DATA: Engineering Test Data for one pedon are published in Soil Survey of Lee County, Mississippi (issued March 1973), pp. 54-55.