Culms 15-40 cm, glabrous or puberulent. Sheaths glabrous or puberulent;
cauline blades 2-5 cm long, 2.5-4.5 mm wide, usually puberulent abaxially
and glabrous adaxially. Primary panicles 2-4.5 cm. Spikelets 1.5-2.0
mm, puberulent to nearly glabrous.
Dichanthelium portoricense subsp. portoricense is more common
than subsp. patulum in coastal sand dunes.
It also grows in sandy pinelands and savannahs. It resembles D.
aciculare somewhat, but that species usually has ascending-pilose culms,
strongly involute or acicular blades, and longer spikelets.