The Reap series consists of deep, well drained, very slowly permeable soils that formed in clayey sediments. These soils are on nearly level to gently sloping uplands. Slopes range from 0 to 3 percent. Thickness of the A and AC horizons ranges from 40 to 70 inches. These soils are calcareous throughout the matrix.
All horizons are clay or silty clay.
The average clay content of the 10 to 40 inch control section ranges from 45 to 60 percent. Intersecting slickensides are distinct beginning at depths of 24 to 36 inches below the soil surface. The accumulation of calcium carbonate ranges from a few concretions and soft bodies to 15 percent by volume. These are the Ferris , Harlingen , Heiden , Indiahoma , Leeray , Lipan , Randall , Roscoe , Stamford , and Tobosa series. Harlingen soils have more than 60 percent clay and average soil temperatures are 72 degrees F., or greater.