LOCATION WATSONIA AL+LAEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, thermic, shallow Leptic Hapluderts
TYPICAL PEDON: Watsonia clay-- on a gently sloping ridgetop in pasture. (Colors are for moist soil.)
Ap--0 to 3 inches; dark yellowish brown (10YR 4/4) clay; weak coarse subangular blocky structure; firm; many fine and very fine roots; moderately acid; abrupt smooth boundary. (1 to 5 inches thick)
Bss1--3 to 10 inches; yellowish red (5YR 5/6) clay; common medium distinct yellowish brown (10YR 5/6) mottles; weak coarse angular blocky which parts to moderate medium subangular and angular blocky structure; very firm; common fine and very fine roots; common large slickensides with distinct polished and grooved faces; moderately acid; clear wavy boundary. (5 to 15 inches thick)
Bss2--10 to 16 inches; light olive brown (2.5Y 5/6) clay; few medium distinct yellowish red (5YR 5/6) mottles; moderate coarse angular blocky structure; very firm; few fine and very fine roots; common large intersecting slickensides with distinct polished and grooved faces; common soft black masses; common soft masses of calcium carbonate at the contact with chalk bedrock; neutral; abrupt wavy boundary. (0 to 10 inches thick)
2Cr--16 to 80 inches; light gray (2.5Y 7/2) chalk bedrock; strong medium and thick platy structure; can be cut with hand tools and is rippable by light machinery; violently effervescent; moderately alkaline.
TYPE LOCATION: Perry County, Alabama; about 2.6 miles south of Tayloe; 800 feet north and 2500 feet east of the southwest corner of Section 26, T.17N., R.6E.
RANGE IN CHARACTERISTICS: Solum thickness and depth to chalk bedrock ranges from 10 to 20 inches.
The A or Ap horizon has hue of 10YR or 2.5Y, value of 3 to 5, and chroma of 1 to 4. Reaction ranges from very strongly acid to slightly acid. Texture is clay or silty clay.
The upper part of the Bss horizon has hue of 2.5YR or 5YR, value of 4 or 5, and chroma of 4 to 8; or it has no dominant matrix color and is mottled in shades of red, brown, and olive. Reaction ranges from very strongly acid to slightly acid. Commonly, the lower part has hue of 10YR or 2.5Y, value of 4 to 6, and chroma of 4 to 8; but also includes the same range in color as the upper part. Mottles, if present, are in shades of red, olive, or brown. Reaction ranges from slightly acid to moderately alkaline. Content of soft masses and/or concretions of calcium carbonate ranges from none to common. Texture of the Bss horizon is clay or silty clay.
A thin Bw horizon is present in some pedons. It has hue of 2.5YR or 5YR, value of 4 or 5, and chroma of 4 to 8. It has the same range in texture and reaction as the upper part of the Bss horizon.
The 2Cr horizon is chalk bedrock. It can be cut with hand tools and is rippable by light machinery. It is strongly or violently effervescent and reaction is moderately alkaline or strongly alkaline.
COMPETING SERIES: There are no other known series in the same family.
GEOGRAPHIC SETTING: Watsonia soils are on narrow, convex ridgetops and on side slopes of the Alabama, Mississippi, and Arkansas Blackland Prairie MLRA. Slopes range from 1 to 25 percent. These soils developed in thin layers of clayey sediments overlying chalk. The climate is warm and humid. The average annual air temperature ranges from 60 to 65 degrees F., and the average annual precipitation ranges from 48 to 56 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Binnsville, Demopolis, Faunsdale, Oktibbeha, Sumter, and Vaiden series. Binnsville soils are on smoother positions and have a mollic epipedon. Demopolis soils are on similar positions as Watsonia and are loamy-skeletal. Faunsdale and Vaiden soils are on smoother positions and are very deep to chalk bedrock. Oktibbeha soils are on similar positions as Watsonia and are very deep to chalk bedrock. Sumter soils are on smoother positions and are moderately deep to chalk bedrock and are calcareous to the surface.
DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; very slow permeability.
USE AND VEGETATION: Most areas have been cleared and are in pasture or hayland. Common crops in cultivated areas are soybeans, corn, and oats. Common trees in wooded areas include loblolly pine, Eastern redcedar, and mixed hardwood.
DISTRIBUTION AND EXTENT: The Blackland Prairie section of Alabama, Louisiana, and Mississippi. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama
SERIES ESTABLISHED: Greene County, Alabama; 1965. Type location moved to Perry County, Alabama, 9/92.
REMARKS: This revision (2/95) changes the classification from Paralithic Vertic Eutrochrepts to Leptic Hapluderts in accordance with amendment to Soil Taxonomy 615.90. This soil will be in a shallow family (and clayey particle-size class) when provided for in the Vertisol order.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 3 inches (Ap)
Cambic horizon: 3 to 16 inches (Bss1 and Bss2)
Hapluderts features: slickensides close enough to intersect; weighted average of 30 percent or more clay throughout; open cracks in most years; pH value of 5.0 or more in 1:1 water in more than 50 percent of the soil volume. 3 to 16 inches (Bss1, Bss2)
Leptic feature: a paralithic contact within 100 cm of the surface; chalk bedrock at 16 inches (2Cr)
SIR = AL0068