LOCATION SILVERDALE MO+MSEstablished Series
TAXONOMIC CLASS: Sandy over loamy, mixed, superactive, nonacid, thermic Aquic Udifluvents
TYPICAL PEDON: Silverdale loamy sand - on a 1 percent slightly concave slope in a cultivated field. Soil was moist throughout when described. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 8 inches; dark brown (10YR 3/3) loamy sand; brown (10YR 5/3) dry; very weak fine granular structure; loose; very friable; few fine roots; moderately acid; abrupt smooth boundary. (7 to 14 inches thick)
C1--8 to 20 inches; brown (10YR 4/3) sand; few fine and medium faint dark yellowish brown (10YR 4/4) and yellowish brown (10YR 5/4) masses of iron accumulation; few fine faint dark grayish brown (10YR 4/2) iron depletions; single grain; loose; slightly acid, clear smooth boundary.
C2--20 to 31 inches; dark grayish brown (10YR 4/2) sand; common fine and medium faint dark yellowish brown (10YR 4/4) masses of iron accumulation; single grain; loose, slightly coherent when moist; few fine dark soft accumulations (oxides); moderately acid; abrupt smooth boundary. (Combined thickness of the C horizons is 13 to 32 inches.)
2C3--31 to 50 inches; grayish brown (10YR 5/2) silt loam; common fine faint brown (10YR 4/3) masses of iron accumulation; massive; friable; slightly acid; clear smooth boundary.
2C4--50 to 63 inches; light brownish gray (10YR 6/2) silt loam; common fine and medium distinct dark yellowish brown (10YR 4/4) masses of iron accumulation; massive; friable; many fine dark soft accumulations (oxides); slightly acid; abrupt smooth boundary. (Combined thickness of the 2C horizons is 16 to 36 inches.)
3C5--63 to 70 inches; brown (10YR 5/3) sand; common fine faint grayish brown (10YR 5/2) mottles; single grain; loose; slightly acid.
TYPE LOCATION: Dunklin County, Missouri; about 3 miles west and 3 miles south of Hornersville; about 1,815 feet west and 150 feet north of center of section 23, T. 16 N., R. 8 E. Latitude 36 degrees, 0 minutes, 37.1 seconds N., longitude 90 degrees, 10 minutes, 27.4 seconds W., NAD83.
RANGE IN CHARACTERISTICS: The sandy sediments typically range from 24 to 39 inches thick. The loamy alluvium ranges from 16 to 36 inches thick.
The Ap horizon has hue of 10YR, value of 3 or 4, and chroma of 2 or 3. Typically it is loamy sand but can be fine sand, sand, loamy fine sand, or sandy loam. The A horizon ranges from strongly acid to neutral.
The C horizon has hue of 10YR or 7.5YR, value of 4 to 6, and chroma of 3 or 4 and mottles with value of 4 to 6 and chroma of 2 or it has matrix color with chroma of 2 or less with brownish mottles. It is fine sand, sand, or coarse sand. It ranges from medium acid to neutral. Some pedons have thin layers and pockets of concretions and oxides (FeMn) in the lower part of the horizon.
The 2C horizon has hue of 10YR or 2.5Y, value of 4 to 6, and chroma of 1 or 2. It is silt loam, silty clay loam, or loam. In some pedons the upper part has a darker colored buried horizon with value of 3 or 4 and chroma of 2 or 3. It commonly is slightly acid but ranges from medium acid to neutral. Mottles have value of 4 to 6 and chroma of 3 or 4.
The 3C horizon has hue of 10YR, value of 4 to 6, and chroma of 2 to 4. It is sand or loamy sand. It is slightly acid or neutral.
COMPETING SERIES: There are no other series in the same family. Similar soils are the Canalou, Crevasse, and Steele series. Canalou soils contain more silt and clay in the upper part of the control section and contain more sand in the lower part of the control section. Crevasse soils are sandy throughout the control section. Steele soils have clayey textures at depths of 20 to 36 inches.
GEOGRAPHIC SETTING: Silverdale soils are nearly level and in slightly concave micro depressions on natural levees in the upper part of the Mississippi River Delta. The soils formed in sandy sediments and loamy alluvium. Mean annual temperature ranges from 59 to 65 degrees F, and mean annual precipitation ranges from 45 to 55 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cairo, Dubbs, Dundee, Gideon, Roellen, and Sikeston soils. All of these soils contain more silt and clay in the upper part of the solum than Silverdale. Cairo, Gideon, Roellen, and Sikeston are in the concave natural drains in nearby landscapes. Dubbs and Dundee soils are on natural levees bordering former channels.
DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff is low. Permeability is rapid in the upper part and moderate in the lower part.
USE AND VEGETATION: These soils are cultivated. Soybeans, wheat, and cotton are the principal crops. Native vegetation is mixed bottom land hardwoods with an understory of vines and grasses.
DISTRIBUTION AND EXTENT: The Mississippi River Valley area (MLRA 131) of southeastern Missouri and western Mississippi. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Dunklin County, Missouri, 1977.
REMARKS: Diagnostic horizons and features recognized in this series are: ochric epipedon - the zone from the surface to a depth of 8 inches (Ap horizon); udic moisture regime.