Bleiblerville, Branyon, Burleson, Dimebox, Fairlie, Houston Black, Leson and Slidell soils have chroma of 1 throughout the upper 12 inches and are on uplands or terraces. Clarita and Tamford soils have hue 7.5YR or redder in the subsoil. Heiden, Luling and Sanger soils have a solum less than 80 inches thick. Watonga soils have a solum less than 60 inches thick. Kaufman and Tinn and Trinity soils have chroma of 1 in the upper 12 inches also Kaufman soils are noncalcareous.
Ovan soils are on nearly level to gently sloping flood plains.
Slopes are mainly less than 1 percent but some are as much as 2 percent. The soil formed in calcareous clayey alluvium. The climate is warm and subhumid. The annual precipitation ranges from 30 to 38 inches and the annual temperature ranges from 64 to 67 degrees F. Frost free days range from 220 to 255. The elevation ranges from 350 to 600 feet above sea level.