LOCATION KETONA AL+GAEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, thermic Vertic Epiaqualfs
TYPICAL PEDON: Ketona silty clay loam--on a concave slope of 1 percent in a pasture at 500 feet elevation.
(Colors are for moist soil.)
A1--0 to 6 inches; very dark grayish brown (10YR 3/2) silty
clay loam; strong medium granular structure; friable; many fine
and medium roots; neutral; clear wavy boundary. (3 to 7 inches thick)
B21tg--6 to 30 inches; gray (10YR 5/1) silty clay, common
coarse distinct light olive brown (2.5Y 5/4), and yellowish brown (10YR 5/6) mottles; moderate coarse angular blocky and weak medium subangular blocky structure; firm; plastic; common fine and medium roots; few fine root pores; thin continuous clay films or pressure faces on faces of peds; few small rounded, limestone fragments;
dark gray silty clay loam surface material fill old cracks; mildly alkaline; diffuse wavy boundary.
B22tg--30 to 50 inches; gray (10YR 6/1) silty clay; many
coarse distinct yellowish brown (10YR 5/6) mottles; moderate
coarse angular blocky structure and weak medium subangular blocky structure; firm; plastic; few fine and medium roots; thin
continuous clay films or pressure faces on faces of peds; few intersecting slickensides; few small, rounded, limestone
fragments; moderately alkaline; abrupt irregular boundary.
(Combined thickness of the B2t horizons is 37 to 65 inches.)
R--50 inches; hard limestone bedrock.
TYPE LOCATION: Jefferson County, Alabama; about 1 mile northeast
of McCalla, 1600 feet south of the NE corner of section 36, T. 19
S., R. 5 W.
RANGE IN CHARACTERISTICS: Solum thickness and depth of limestone bedrock ranges from 40 to more than 60 inches. Reaction ranges
from slightly acid to moderately alkaline in all horizons. Some pedons have recent alluvial sediments deposited over the A1
horizons. All horizons except the recent alluvial layers crack
when dry. Many pedons contain small, round, brown, or black concretions and limestone fragments.
The A1 or Ap horizon has hue of 10YR, value of 2 through 4, and chroma of 1 through 3. Texture is silty clay, silty clay loam, or silt loam.
The A2 or B1 horizon, where present, is silt loam, silty clay
loam, or clay loam. These horizons have hue of 10YR, 2.5Y, or neutral, value of 4 through 6, and chroma of 2 or less.
The B2t horizon has hue of 10YR, 2.5Y, or neutral, value of 3
through 6, and chroma of 2 or less, or it is mottled in shades of brown, gray, and yellow. Texture is clay or silty clay. In some pedons, the percent of mottles increases with depth.
COMPETING SERIES: The
Pocola series is the only other series in
the same family. Pocola soils are not underlain by limestone
bedrock and are somewhat poorly drained. In addition, Pocola
soils lack clay decreases of more than 20 percent within 60 inches and have perched water tables.
Dowellton soils are similar to
Ketona soils except they are in a very fine textural class.
GEOGRAPHIC SETTING: Ketona soils are on flood plains,
drainageways of upland flats, and depressional areas in limestone valleys. Slope is dominantly 0 to 2 percent, but ranges to 4 percent. These soils formed in old clayey alluvium and residuum
from limestone. Mean annual precipitation is about 53 inches and mean annual temperature is about 62 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are
Bodine,
Collegedale,
Decatur,
Fullerton,
Sullivan, and
Tupelo series. Bodine, Collegedale, Decatur, and Fullerton soils are on uplands, do not
have seasonal water tables, and do not have matrix chroma of 2 or less in their argillic horizon. Sullivan soils are on adjacent
flood plains, are fine loamy, and do not have matrix chroma of 2
or less in the upper part of the solum. Tupelo soils are on
upland flats, are somewhat poorly to moderately well drained, and have a subhorizon with matrix chroma of 3 or more.
DRAINAGE AND PERMEABILITY: Poorly drained. Runoff and
permeability are slow. A seasonal water table is at or near the surface during winter and spring. These soils are subject to frequent brief flooding due to stream overflow or ponding due to
slow runoff or lack of drainage outlets.
USE AND VEGETATION: Most areas of Ketona soils are used for
hardwood forest and pastureland. Some areas have been converted
to urban use.
DISTRIBUTION AND EXTENT: Limestone valleys of Alabama. Possible
in Tennessee. Ketona soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Jefferson County, Alabama, 1980.
REMARKS: Ketona soils were considered to be in the Dowellton
series in the past but characterization data indicates that these soils are in the fine family texture class.
ADDITIONAL DATA: Characterization data is available on samples
from 2 pedons and Alabama Highway Department test data for the typical pedon is available.