LOCATION MONTEVALLO AL+AR GA KY MD TNEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, subactive, thermic, shallow Typic Dystrudepts
TYPICAL PEDON: Montevallo channery silt loam, steeply sloping, forested. (Colors are for moist soil.)
A1--0 to 2 inches; very dark gray (10YR 3/1) channery silt loam, upper 1/2 inch black (10YR 2/1) and high in humus; moderate fine granular structure; friable; many fine roots; strongly acid; clear wavy boundary. (0 to 3 inches thick)
A2--2 to 6 inches; dark grayish brown (10YR 4/2) channery silt loam; weak fine granular structure; friable; many fine and medium roots; strongly acid; lower 2 inches is mixed with from 5 to 15 percent material like that of the B horizon; gradual wavy boundary. (3 to 7 inches thick)
B--6 to 16 inches; yellowish brown (10YR 5/4) extremely channery silt loam; weak fine subangular blocky structure; friable; common fine roots; few large roots; about 70 percent by volume of channers of silty shale; strongly acid; gradual irregular boundary. (4 to 15 inches thick)
Cr--16 to 36 inches; light yellowish brown (10YR 6/4) weakly cemented, fractured silty shale containing less than 5 percent by volume of fines as coatings on shale channers and as siftings in cracks.
TYPE LOCATION: Jefferson County, Alabama; 2 miles west of Graysville, 0.6 mile south-southwest of Flattop Experimental Forest Office and 50 feet east of gravel road in timer in N1/2SW1/4 sec. 19, T. 16 S., R 4 W.
RANGE IN CHARACTERISTICS: Solum thickness and depth to rock range from 10 to 20 inches thick. Reaction ranges from medium acid to very strongly acid, except for the surface layer where limed.
The A horizon has hue of 7.5YR or 10YR, value of 2 through 6, and chroma of 1 to 4. Where value is less than 4, the A horizon is less than 6 inches thick. The A horizon contains 15 to 60 percent by volume of channers of shale. Texture is channery silt loam, channery loam, very channery silt loam, or very channery loam.
The B horizon has hue of 2.5Y through 5YR, value of 4 through 6, and chroma of 3 through 8. The B horizon contains 35 to 85 percent shale channers. Texture is very channery silt loam, very channery loam, very channery clay loam, very channery silty clay loam, or their extremely channery counterparts. Percent clay ranges from 15 to 35 percent.
The Cr is weakly cemented siltstone or silty shale that is in beds having dip of less than 35 degrees. Hardness of this material on Moh's scale ranges from 1.5 to 3.0.
COMPETING SERIES: There are no other known series in this family. Other competing series in related families are the Armuchee, Hector, Manteo, Mountainburg, Pickens, Ramsey, Sulphura, Tallapoosa, and Talladega series. Armuchee soils contain more than 35 percent clay and less shale fragments in the sola. Hector, Manteo, Mountainburg, Pickens, Ramsey, Sulphura, and Talladega soils have a lithic contact at depths of 20 inches or less. In addition, Hector and Ramsey soils contain less than 35 percent coarse fragments. Mountainburg soils have Bt horizons. Sulphura soils have Bt horizons in some parts of each pedon, and Talladega soils have loamy Bt horizons interrupted by rock ledges. Tallapoosa soils have thin continuous Bt horizons.
GEOGRAPHIC SETTING: Montevallo soils are on gently sloping to steep valley slopes and narrow ridgetops of the southern Appalachian Region. Slope gradients range from 2 to 45 percent. The soil formed in residuum from siltstone or silty shale which may contain a few strata of sandstone. The climate is warm and humid. Near the type location, the average daily temperature for January is 47 degrees F., that for July is 81 degrees F., and the mean annual temperature is about 63 degrees F. The mean annual precipitation is about 53 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Ramsey series, and the Albertville, Cunningham, Enders, and Townley series. Albertville, Cunningham, Enders, and Townley soils have clayey Bt horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderate permeability.
USE AND VEGETATION: Chiefly used for forestry. Native trees are hickory, red oak, white oak, blackjack oak, shortleaf pine, longleaf pine, and Virginia pine. Small acreages are used for pasture, hay, and cultivated crops.
DISTRIBUTION AND EXTENT: Alabama, Arkansas, Georgia, Tennessee, and possibly other states. The series is of large extent.
MLRA OFFICE RESPONSIBLE: Lexington, Kentucky
SERIES ESTABLISHED: Talladega County, Alabama; 1907.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface to a depth of 6 inches (the A1 and A2 horizons)
Cambric horizon - the zone from a depth of 6 inches to a depth of 16 inches (the Bt horizon)
Paralithic contact - the contact of the soil with silty shale (16 inches)