It is sandy clay loam, loam, or fine sandy loam. Concretions, soft masses, threads, and films of calcium carbonate range from few to many. These include the Cisco series in the same family and Altus , Cobb , Devol , Duffau , Grandfield , and Konawa series in similar families. Altus soils have mollic epipedons thicker than 20 inches and occur in a drier climate. In addition, Cobb, Grandfield, and Konawa soils have mixed mineralogy.
Devol soils have coarse-loamy control sections.
May soils are on nearly level stream terraces or shallow upland valleys with plane or concave surfaces. Slope gradients are 0 to 3 percent. The soils formed in local, loamy alluvium. Mean annual temperature is 64 to 67 degrees F., average annual precipitation is 26 to 40 inches, and Thornthwaite P-E indices are 40 to 64. These are the competing Cisco and Duffau , and the Bosque , Nimrod , Pedernales , and Windthorst series.