LOCATION BROOKSVILLE MS+ALEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Aquic Hapluderts
TYPICAL PEDON: Brooksville silty clay loam, nearly level in pasture. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 6 inches; very dark grayish brown (2.5Y 3/2) silty clay loam; moderate medium granular structure; friable; plastic; few fine roots; few fine brown concretions; neutral; abrupt smooth boundary.
A1--6 to 16 inches; dark olive gray (5Y 3/2) silty clay loam; few fine prominent yellowish red (5YR 5/6) mottles; moderate medium prismatic structure parts to moderate medium and fine angular blocky; firm, very sticky, very plastic; few fine roots; few fine brown and black concretions; medium acid; clear wavy boundary.
A2--16 to 32 inches; dark grayish brown (2.5Y 4/2) silty clay; many fine prominent red (2.5YR 4/6) mottles; moderate medium prismatic structure parts to moderate fine and medium angular blocky; firm, very sticky, very plastic; few fine roots; few fine brown and black concretions; medium acid; clear wavy boundary. (Combined thickness of the A horizon is 18 to 38 inches.)
Bw1--32 to 39 inches; dark grayish brown (2.5Y 4/2) silty clay; many fine faint olive brown (2.5Y 4/4) mottles; intersecting slickensides 3- to 4-inch cross-section form wedge shaped aggregates which part to moderate, fine and medium angular blocky structure; firm, very sticky, very plastic; few fine roots; few fine brown and black concretions; mildly alkaline; gradual wavy boundary.
Bw2--39 to 50 inches; dark grayish brown (2.5Y 4/2) silty clay; many fine faint light olive brown (2.5YR 5/4) mottles; intersecting slickensides 3- to 4-inch cross-section form wedge shaped aggregates which part to moderate fine and medium angular blocky structure; very firm, very sticky, very plastic; few fine roots; few brown and black concretions; few lime nodules; slightly effervescent, moderately alkaline; gradual wavy boundary.
Bw3--50 to 68 inches; light olive brown (2.5Y 5/4) silty clay; many fine faint yellowish brown (10YR 5/6) and dark grayish brown (10YR 4/2) mottles; intersecting slickensides 4- to 16-inch cross-section form wedge shaped aggregates which part to moderate fine and medium angular blocky structure; very firm, very sticky, very plastic; few brown and black concretions; few coarse lime nodules; strongly effervescent, moderately alkaline; gradual wavy boundary. (Combined thickness of the Bw horizon is 22 to 46 inches.)
C--68 to 82 inches; mottled yellowish brown (10YR 5/6) and gray (N 5/0) silty clay; intersecting slickensides form wedge shaped aggregates which part to moderate medium angular blocky structure; very firm, very sticky, very plastic; many fine and medium black concretions; few coarse lime nodules; strongly effervescent, moderately alkaline.
TYPE LOCATION: Chickasaw County, Mississippi; 0.5 mile east of U.S. Highway 45 at Egypt, 1.95 miles north and 200 feet west into pasture, NE1/4NE1/4 sec. 25, T. 13 S., R. 5 E.
RANGE IN CHARACTERISTICS: Thickness of the solum horizons ranges from 40 to more than 70 inches. Intersecting slickensides are at a depth ranging from 18 to 38 inches below the surface. Cycles of micro-lows and micro-highs are repeated about every 7 to 20 feet. Thickness of horizons with a color value of less than 3.5 and chroma of 1.5 or more ranges from 16 to 25 inches in the center of the micro-lows and from 6 to 14 inches in the center of the micro-highs. The extremes of amplitude or waviness of the boundary between the A and Bw horizons vary from 8 to 38 inches from the center of the micro-highs to the center of the micro-lows.
The A horizon has hue of 10YR, value of 2 or 3, and chroma of 2 or 3, or it has hue of 2.5Y or 5Y with value of 3, and chroma of 2 in the upper 12 inches in more than half of each pedon; also allowed are hue of 10YR, value of 3, and chroma of 1 and hue of 10YR, 2.5Y and 5Y, value of 4 and chroma of 2. Few to many distinct and prominent mottles of red, yellowish red, and dark yellowish brown are within 20 inches of the surface. The Ap and A1 horizons are silty clay loam or silty clay; and the A2 horizon is silty clay or clay. The A horizon is strongly acid to slightly acid, except in areas where the surface layer has been limed.
The Bw subhorizons and the C horizon have hue 2.5Y or 5Y, value of 4 or 5, and chroma of 2 to 4, or hue of 10YR, value of 4, and chroma of 2, or they are mottled in shades of the above colors. The Bw and C horizons are silty clay or clay. The 10- to 40-inch particle-size control section has 35 to 55 percent clay. The Bw and C horizons are neutral to moderately alkaline. Brown and black concretions commonly are few to many in the A and Bw horizons. Few to many lime nodules are in the lower part of the Bw and C horizons.
COMPETING SERIES: These are the Terouge and Zilaboy series in the same family and the similar Beaumont, Houston, Kipling, Okolona, Sumter, and Vaiden series. Terouge soils are neutral to moderately alkaline throughout. Zilaboy soils have a summer moisture deficit of more than 5 inches and, in addition, are on flood plains. Beaumont soils have chroma of less than 1.5 and are grayer throughout. Houston soils do not have distinct or prominent mottles in the upper 20 inches, have more than 60 percent clay in the 10- to 40-inch particle-size control section, and are less acid in upper part of the solum. Kipling soils have a Bt horizon that is typically yellowish brown. Okolona soils do not have distinct or prominent mottles within 20 inches of the surface. Sumter soils do not have intersecting slickensides, are shallower to chalk, and are calcareous. Vaiden soils have a moist color value of more than 3.5 in the A horizon, are more acid in the upper part of the solum, and have more than 60 percent clay in the control section.
GEOGRAPHIC SETTING: Brooksville soils are on uplands in the Blackland Prairie Major Land Resource Area. These are nearly level to gently sloping soils that formed in acid clay or silty clay underlain by calcareous materials or chalk. Slopes range from 0 to 5 percent. The climate is warm and humid. Average annual precipitation is about 48.0 inches and average annual temperature is about 63.0 degrees Fahrenheit near the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Houston, Kipling, Okolona, Sumter, and Vaiden series of the competing series and the Griffith series. Houston, Kipling, Okolona, and Vaiden soils are in similar landscape positions as the Brooksville soils. Griffith soils, which are on flood plains, have amplitude of waviness between the A and Bw horizons of 6 to 10 inches and the A horizon is 24 to 48 inches thick.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow to rapid runoff; very slow permeability. A water table is perched at a depth of 2 to 4 feet during wet seasons late in winter and early in spring.
USE AND VEGETATION: Most areas of the Brooksville soils are used for growing cotton, soybeans, sorghum, small grains, hay, and pasture. Common trees are eastern redcedar and osage orange.
DISTRIBUTION AND EXTENT: Mississippi and Alabama. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama
SERIES ESTABLISHED: Noxubee County, Mississippi; 1950.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface to a depth of about 16 inches (Ap, A1 horizons).
Cambic horizon - the zone from approximately 32 to 68 inches (Bw1, Bw2, Bw3 horizons).
Chromuderts features - a matrix color that has chroma, moist of 1.5 or more dominant in some subhorizon in the upper 12 inches in more than half of each pedon (Ap, A1 horizon).
Aquic feature - has distinct or prominent mottles within 20 inches of the soil surface in more than half of each pedon (Ap, A1, A2 horizons).
ADDITIONAL DATA: Laboratory data: Engineering test data for one pedon are published in Soil Survey of Chickasaw County, Mississippi (issued March 1974), pp, 40-41. Characterization data for one pedon--S65 Miss9-2-(1-10)--from Chickasaw County, Mississippi are from Soil Survey Laboratory, Beltsville, Maryland.