Houston Black soils have moist value of less than 3.5 and chroma of less than 1.5 throughout the upper 12 inches. Altoga, Ellis, and Lamar soils are on similar positions with Ferris. Heiden and Houston Black soils are on smoother slightly higher positions. Permeability is very slow. Runoff is medium on 1 to 3 percent slopes, high on 3 to 5 percent slopes, and very high on slopes greater than 5 percent.
Infiltration is rapid when the soil is dry and cracked, but very slow when the soil is wet.
Most areas have been cultivated, eroded and are now in grass. Vegetation is mainly bluestems, buffalograss and threeawn grasses and scattered mesquite trees. The series is of large extent, comprising more than 100,000 acres. Ochric epipedon - the A horizon from 0 to 8 inches. Cambic horizon - 8 to 40 inches.