What type of grass is this that grows in dry, sandy soil?
this grass is one of the species of crabgrass, Digitaria sp., either Digitaria filiformis or Digitaria sanguinalis. They can be abundant in disturbed areas. Digitaria filiformis has a three-sided unwinged rachis, and D. sanguinalis has a less triangular winged rachis. The latter is the most common.
Dr. Steven Hill, Botanist, SCNPS