LOCATION TREBLOC MS+AR NCEstablished Series
TAXONOMIC CLASS: Fine-silty, siliceous, active, thermic Typic Paleaquults
TYPICAL PEDON: Trebloc silt loam--forest.
(Colors are for moist soil unless otherwise stated.)
A--0 to 2 inches; very dark gray (10YR 3/1) silt loam; weak fine granular structure; friable; many fine and medium roots; few medium black concretions; many fine wormcasts; very strongly acid; clear smooth boundary. (1 to 6 inches thick)
E--2 to 5 inches; mottled gray (10YR 5/1), light brownish gray (10YR 6/2), and strong brown (7.5YR 5/8) silt loam; weak fine subangular blocky structure; friable; many fine and medium roots; few medium black concretions; very strongly acid; clear wavy boundary. (0 to 8 inches thick)
Btg1--5 to 12 inches; gray (10YR 5/1) silt loam, common medium distinct yellowish brown (10YR 5/6), and light yellowish brown (2.5YR 6/4) mottles; weak medium subangular blocky structure; friable; few fine roots; few medium black concretions; few fine pores; few silt coatings and clay films on faces of peds; very strongly acid; clear wavy boundary.
Btg2--12 to 23 inches; gray (10YR 6/1) silty clay loam, few medium distinct yellowish brown (10YR 5/8), and light yellowish brown (2.5Y 6/4) mottles; weak medium subangular blocky structure; firm; few fine roots; few fine black concretions; few thin silt coatings and patchy clay films on faces of peds; very strongly acid; clear wavy boundary.
Btg3--23 to 35 inches; gray (10YR 6/1) silty clay, common medium distinct yellowish brown (10YR 5/8), and olive yellow (2.5YR 6/6) mottles; moderate medium subangular blocky structure; firm; few fine roots; few fine black concretions; few silt coatings and patchy clay films on faces of peds; very strongly acid; gradual smooth boundary.
Btg4--35 to 65 inches; light gray (2.5Y 7/2) silt clay loam, common medium faint pale yellow (2.5Y 7/4), and common medium distinct strong brown (7.5YR 5/6) mottles; moderate medium subangular blocky structure; firm; few fine roots; few fine black concretions; few silt coatings and patchy clay films on faces of peds; very strongly acid. (Combined thickness of the Btg subhorizons is 54 to 70 inches.)
TYPE LOCATION: Lamar County, Mississippi; located 0.25 mile southwest of Black Creek Bridge on Mississippi Highway 589, SE1/4NW1/4 sec. 12, T. 3 N., R. 15 W.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to 80 inches. Reaction of all horizons is very strongly acid or strongly acid, except in areas where the layer has been limed.
The A horizon has hue of 10YR or 2.5Y, value of 2 to 5, and chroma of 1 or 2. It is silt loam, loam, or fine sandy loam.
The E horizon, if present, (in some pedons plowing has mixed the A and E horizons to form an Ap horizon) has hue of 10YR or 2.5Y, value of 5 or 6, and chroma of 1 or 2, or it is mottled in shades of gray and brown. It is fine sandy loam, loam, or silt loam.
The upper part of the Btg horizon has hue of 10YR, 2.5Y, or 5Y, value of 4 to 7, and chroma of 1 or 2, or it is neutral with value of 5 or 6, and chroma of 0; mottles in shades of yellow and brown range from few to many. The lower part of the Btg horizon has the same range in colors, or it is mottled in shades of gray and brown. The Btg horizon is silt loam, silty clay loam, or silty clay. The particle size control section, upper 20 inches of Btg horizon, has 20 to 32 percent clay and 35 to 55 percent silt. Black concretions range from few to many in the Btg horizon.
COMPETING SERIES: The Grantham is the only series in the same family. Similar series include the Adaton, Amy, Coxville, Daleville, Grady, Leaf, Lenoir, Myatt, Nahunta, Rains, Smithton, Sylacauga, Vimville, and Weston soils. Grantham soils are presumed to have mineralogical or chemical differences. They are on nearly level uplands typically have lower silt content in the upper 20 inches of the argillic horizon and have higher average yields. Adaton soils have more than 35 percent base saturation at 30 inches below the upper boundary of the Bt horizon. Amy soils have a Bt horizon in which the clay decreased by more than 20 percent from the maximum within a depth of 60 inches of the surface. The Coxville, Grady, Leaf, and Lenoir soils are clayey in the control section. Daleville and Vimville soils are fine-loamy in the control section. Myatt soils have a solum less than 60 inches thick, and have a fine-loamy control section. Nahunta and Sylacauga soils are not as gray in the upper part of the B horizon. Rains soils have less than 20 percent silt in the upper 20 inches of the Bt horizon. Smithton and Weston soils have a coarse-loamy particle size class; also Weston soils have a solum less than 60 inches thick.
GEOGRAPHIC SETTING: Trebloc soils formed in medium to moderately fine textured marine or fluvial sediment. These nearly level soils are on stream terraces and in depressions and drainage ways of the uplands of the Southern Coastal Plain and East Gulf Coast Flatwoods. Slopes range from 0 to 2 percent, and the surfaces are plane to slightly concave. The climate is warm and humid. Mean annual temperature is 66 degrees F., and mean annual precipitation is 59 inches near the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Leaf, Nahunta, and Smithton and the Aycock, Exum, Kingston, Mantachie, Mashulaville, Savannah, and Stough soils. Poorly drained Leaf and Smithton soils and somewhat poorly drained Nahunta soils are on similar landscape positions as the Trebloc soils. Well drained Aycock and moderately well drained Exum soils, which are on slightly higher terrain, have a browner Bt horizon. Poorly drained Kingston and somewhat poorly drained Mantachie soils, which are on flood plains, do not have a Bt horizon. Poorly drained Mashulaville soils, which are in depressions to very gently sloping uplands, have a fragipan. Moderately well drained Savannah soils, which are in slightly higher positions, have a fragipan. Somewhat poorly drained Stough, soils which are in similar positions as the Trebloc soils, commonly have better surface drainage, and are browner.
DRAINAGE AND PERMEABILITY: Poorly drained; slow to very slow runoff; slow permeability. The water table is within 0.5 to 1.0 foot of the surface in wet seasons late in winter and early in spring. Most areas of this soil are subject to rare, occasional, or frequent flooding for very brief periods.
USE AND VEGETATION: These soils are mainly in forests of water oak, maple, sweetgum, ash, cypress, and pine trees. Some cleared areas are used for growing pasture and hay.
DISTRIBUTION AND EXTENT: Arkansas, Louisiana, Mississippi, and North Carolina. The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama
SERIES ESTABLISHED: Lamar County, Mississippi; 1969.