LOCATION OPENLAKE TN+KY MS
Established Series
SEM:RPS; Rev.JDS
10/2018
OPENLAKE SERIES
The Openlake series consists of very deep, somewhat poorly drained, very slowly permeable soils that formed in thick deposits of clayey alluvium on flood plains of the lower Mississippi River. These level to undulating soils are in slackwater areas of moderate local relief. Slopes are dominantly 0 to 2 percent, but range to 5 percent. Mean annual precipitation is 51 inches and mean annual temperature is 59 degrees F. near the type location.
TAXONOMIC CLASS: Fine, smectitic, nonacid, thermic Vertic Epiaquepts
TYPICAL PEDON: Openlake silty clay in a soybean field. (Colors are for moist soil.)
Ap1--0 to 5 inches; very dark grayish brown (10YR 3/2) silty clay; moderate fine granular structure; firm, plastic, sticky; common fine roots; slightly acid; abrupt smooth boundary.
Ap2--5 to 7 inches; very dark grayish brown (10YR 3/2) silty clay; few fine faint brown mottles; weak medium angular blocky structure; very firm, plastic, sticky; few fine roots; slightly acid; abrupt smooth boundary. (Combined thickness of A horizon is 3 to 9 inches.)
Bgl--7 to 13 inches; dark grayish brown (10YR 4/2) clay; common fine distinct brown (7.5YR 4/4) and few fine faint gray mottles; weak medium and fine angular blocky structure; very firm, plastic, sticky; few fine roots; shiny faces on some peds; moderately acid; gradual smooth boundary.
Bg2--13 to 26 inches; dark grayish brown (10YR 4/2) silty clay; common fine distinct brown (10YR 4/3) and dark yellowish brown (10YR 4/4) mottles; moderate medium angular blocky structure parting to moderate fine angular blocky; very firm, very plastic, very sticky; few fine roots; shiny faces on some peds; few slickensides; moderately acid; gradual smooth boundary.
Bg3--26 to 43 inches; dark grayish brown (10YR 4/2) silty clay; dark gray (10YR 4/1) ped faces; common medium faint brown (10YR 4/3) and very dark grayish brown (10YR 3/2) mottles; moderate medium angular blocky structure parting to moderate fine angular blocky; very firm, very plastic, very sticky; few fine roots; shiny faces on many peds; few slickensides; moderately acid; diffuse smooth boundary.
Bg4--43 to 68 inches; dark grayish brown (10YR 4/2) silty clay; dark gray (10YR 4/1) ped faces; common fine distinct brown (10YR 4/3) and dark yellowish brown (10YR 4/4) mottles; moderate medium angular blocky structure parting to moderate fine angular blocky; very firm, very plastic, very sticky; few fine roots; shiny faces on many peds; few slickensides; neutral; diffuse smooth boundary. (Combined thickness of the Bg horizon is 27 to 76 inches.)
Cg--68 to 75 inches; gray (10YR 5/1) clay; common fine distinct dark yellowish brown (10YR 4/4) mottles; massive; very firm, very plastic, very sticky; neutral.
TYPE LOCATION: Lauderdale County, Tennessee; 1.1 miles south of Tennessee Highway 19 on Conner Road, then west 3,600 feet on Daniels Road, then 850 feet north into a cultivated field.
RANGE IN CHARACTERISTICS: The thickness of the solum ranges from 37 to 80 inches. Cracks l to 2 cm wide develop to a depth of 50 to 75 cm in most years.
The A horizon has hue of 10YR or 2.5Y, value of 3 or 4 and chroma of l to 3. Texture is silty clay, clay, or silty clay loam. Reaction is strongly acid to slightly alkaline.
The Bg horizon has hue of 10YR or 2.5Y, value of 4 or 5 and chroma of 2 with few to many mottles in shades of brown and red. Some pedons have a chroma of 3 above a depth of 20 inches. Some pedons have subhorizons with chroma of 1 or have faces of peds with chroma of 1 below depths of 20 inches. Texture is silty clay or clay. Some pedons have thin subhorizons of silty clay loam or silt loam. Structure is moderate or weak angular blocky or subangular blocky. Reaction is strongly acid to mildly alkaline, but at least one subhorizon within a depth of 40 inches is less acid than strongly acid.
Some pedons have a buried A horizon with hue of 10YR, value of 3 or 4 and chroma of 1 or 2. Texture is clay, silty clay, or silty clay loam. Reaction is strongly acid to slightly alkaline.
The Cg horizon has hue of 10YR, 2.5Y, or 5Y, value of 4 to 6 and chroma of 1 or 2 or it is neutral with value of 4 to 6. Mottles are none to many in shades of brown or red. Texture is typically clay or silty clay, but some pedons have coarser textures below 40 inches. Mica flakes are commonly visible in the coarser textured strata. Reaction is moderately acid to slightly alkaline.
COMPETING SERIES: These are the
Gladewater,
Kobel, and
Leeper series. Series in closely related families are the
Alligator,
Earle,
Harahan,
Houlka,
Keyespoint,
Osage,
Perry,
Sharkey,
Tuscumbia,
Tunica and
Una. Gladewater and Kobel soils are poorly drained with chroma of less than 2. Leeper soils typically have a thinner solum, do not range to strongly acid and have higher value in the A horizon. In addition, Leeper soils formed in alluvium washed from soils in the Blackland Prairies and have shorter duration of flooding. Alligator, Harahan, Perry, and Sharkey soils are poorly drained and have a very fine particle-size control section. In addition, Alligator soils are in an acid family. Earle, Keyespoint, and Tunica soils have a clayey over loamy particle-size control section and the Earle series is in an acid family. Houlka soils are in an acid family. Osage soils have a mollic epipedon 24 to 40 inches thick. Tuscumbia and Una soils are poorly drained and have mixed mineralogy.
GEOGRAPHIC SETTING: Openlake soils are on broad, level to undulating flood plains of the lower Mississippi River. They formed in recent clayey alluvium in slackwater areas with moderate local relief. The slope gradient most commonly is 0 to 2 percent, but the range is 0 to 5 percent. The mean annual precipitation is 51 inches and mean annual temperature is 59 degrees F. near the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing
Keyespoint,
Sharkey, and
Tunica series and the
Bowdre and
Commerce series. Bowdre soils have a clayey over loamy control section and have a mollic epipedon. Commerce soils are fine-silty and have mixed mineralogy.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; very slow permeability. This soil is most often flooded in the winter and early spring and can remain flooded for several days to a month. The water table is within 1 to 2 feet of the surface during the winter and early spring.
USE AND VEGETATION: Most areas of this soil are cleared and cultivated. Soybeans are the major crop with small acreages of cotton, corn, and wheat grown mostly at higher elevations. Some fairly large areas remain in bottomland hardwood forest.
DISTRIBUTION AND EXTENT: The Mississippi River flood plain in Arkansas, Kentucky, Louisiana, Mississippi, Missouri and Tennessee. The acreage is of moderate extent. There are approximately 10,000 acres in Lauderdale County, Tennessee.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: AUBURN, ALABAMA
SERIES ESTABLISHED: Lauderdale County, Tennessee, 1985.
REMARKS: Diagnostic horizons recognized in this pedon are;
Ochric epipedon - 0 to 7 inches (Ap horizon)
Cambic horizon - 7 to 68 inches (Bg horizon)
These soils need more study to determine if there are slickensides and wedge-shaped aggregates that meet the requirements for Vertisols.
Openlake soils were formerly included in the Sharkey series.
ADDITIONAL DATA: Particle size, pH, CEC, and extractable cations were determined for 3 pedons by the University of Tennessee.
National Cooperative Soil Survey
U.S.A.