LOCATION PRIM                    AL

Established Series
Rev. GWH
10/2018

PRIM SERIES


The Prim series consists of shallow, well drained, moderately slowly permeable soils that formed in outcrops of soft limestone or chalk on dissected landscapes in the Coastal Plain. Slopes range from 4 to 40 percent.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, thermic, shallow Typic Haprendolls

TYPICAL PEDON: Prim cobbly clay loam--forested. (Colors are for moist soil.)

A--0 to 7 inches; black (10YR 2/1) very cobbly clay loam; moderate medium granular structure; friable; slightly sticky; many fine roots; about 40 percent by volume of chalk and hard limestone fragments ranging from 2 mm to 30 cm in diameter; strong effervescence; mildly alkaline; clear smooth boundary. (4 to 10 inches thick)

C--7 to 15 inches; olive gray (5Y 5/2) extremely cobbly sandy loam; weak granular structure; friable, slightly sticky; few fine calcium carbonate concretions; about 60 to 70 percent by volume light gray (5Y 7/2) chalk fragments that range from 2 mm to 35 cm in diameter; few distinct streaks of olive yellow in soil material and in chalk fragments; few fine and medium roots in soil material between fracture faces; strong effervescence; mildly alkaline; gradual wavy boundary. (0 to 10 inches thick)

Cr--15 to 60 inches; light gray (5Y 7/2) soft chalk; few fine steaks or splotches of olive yellow; very weak platy structure to massive; can be cut with spade; common fine calcium carbonate concretions; strong effervescence; moderately alkaline.

TYPE LOCATION: Clarke County, Alabama; approximately 3.5 miles north, northwest of Barlow Bend, Alabama, in the SE1/4NE1/4SE1/4 sec. 10, T. 6 N., R. 4 E. Site located approximately 1800 feet north and 150 feet southeast of corner of section 10.

RANGE IN CHARACTERISTICS: Thickness of the soil over continuous chalk ranges from 4 to 20 inches. The chalk has a hardness of less than 3 on Mohs scale and can be dug with a spade. Limestone fragments cover from 20 to 70 percent of the surface. They range from 5 to 45 cm in diameter but are usually less than 25 cm. They are hard limestone and are known locally as "horse-bone rock." The soil is calcareous throughout. Reaction is mildly or moderately alkaline.

The A horizon has hue of 10YR or 2.5YR, value of less than 3.5, and chroma of 3 or less. Texture is very cobbly loam, very cobbly silty clay loam, or very cobbly clay loam; or their extremely cobbly analogues. Thickness of the A horizon is 10 inches or less. Content of limestone fragments range from 35 to 70 percent by volume and range from 2 mm to 30 cm in diameter. Fine concretions of calcium carbonate range from none to few.

The C horizon, where present, has hue of 10YR, 2.5Y, or 5Y, value of 4 or more, and chroma of 1 through 3. This horizon may contain a few mottles of yellowish brown or olive yellow. Texture is very cobbly loam, very cobbly sandy loam, or very cobbly clay loam; or their extremely cobbly analogues. Chalk fragments range from 40 to 90 percent by volume and range from 2 mm to 40 cm in diameter. Fine concretions of calcium carbonate range from none to common.

The Cr horizon has hue of 10YR, 2.5Y, or 5Y, value of 5 or more, and chroma of 1 through 3. Texture of the chalk is loam, sandy loam, or clay loam. Splotches or streaks of yellowish brown, olive yellow, yellow, and pale olive in the chalk range from none to common. This horizon may be interbedded with layers of harder limestone up to 14 inches thick. These layers have the same colors as do the chalk but they are more difficult to cut with a spade. Thickness of continuous chalk or limestone is usually greater than 6 feet. Structure is usually massive but may be weak platy in some pedons. Fine calcium carbonate concretions range from none to common.

COMPETING SERIES: There are no other series in this taxonomic class. Demopolis soils, in a related family, have values of 4 or more in the surface layer.

GEOGRAPHIC SETTING: Prim soils are on outcrops of soft limestone or chalk within the Coastal Plain. The landscape is dissected, and slopes are mainly 10 to 35 percent, but range from 4 percent on the ridgetops to 40 percent on the steeper side slopes. The outcrops are primarily from the Byram or Marianna formation. Near the type location, the annual precipitation is 56 inches and the mean annual temperature is 64 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Luverne, Bama, and Troup series which form perimeters around the outcrop areas. Luverne soils have more than 35 percent clay in the control section and are acid in reaction. Bama soils have thick Bt horizons and are acid in reaction. Troup soils have thick sandy epipedons. Also associated are Oktibbeha and Watsonia soils. These soils have acid subsoils.

DRAINAGE AND PERMEABILITY: Prim soils are well drained. Runoff is rapid and permeability is moderately slow.

USE AND VEGETATION: Most areas are in forest of redcedar and mixed hardwoods. The more gently sloping areas are used for pastures of fescue and clovers and small grains. Many cut-over and idle areas are in naturally revegetated redcedars and hardwoods.

DISTRIBUTION AND EXTENT: Coastal Plain of Alabama and possibly Mississippi. The series is believed to be moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama

SERIES ESTABLISHED: Monroe County, Alabama; 1984.

REMARKS: These soils have been included within the Demopolis series.

ADDITIONAL DATA: Sample No. S77AL-25-18, NSSL number 77P1240-77P1242.


National Cooperative Soil Survey
U.S.A.