Heteropogon melanocarpus

H. melanocarpus is a coarse annual grass with glabrous culms ranging from 0.8 to 2 meters tall. Leaves are primarily cauline, with blades up to 40 cm long and about 1 cm wide. The upper surface near the collar region is long-pilose, margins are slightly rough, and sheaths are mostly glabrous, sometimes glandular, with the upper sheaths inflated and often scarious along the margins. Ligules are membranous, lacerate, and measure 2–4 mm in length. The inflorescence consists of compact, pedunculate racemes that emerge from the inflated upper sheaths. Racemes are 2–4 cm long (excluding awns). Each contains a fertile and staminate sessile spikelet paired with a staminate, pedicellate spikelet. The first glume of the pedicellate spikelet is asymmetric, prominently nerved, acuminate, and 12–17 mm long, with one margin winged and glandular-punctate; the second glume is membranous and similar in shape. Fertile and sterile lemmas are hyaline and reduced, lacking a palea. The awn of the fertile lemma is twisted, genticulate, brown-hirsute, and can reach up to 10 cm in length. The callus is appressed, brown-hirsute, and 2–3 mm long. Grains are yellowish, linear, cylindrical (terete), and approximately 4 mm in length.^[1]

In the United States, H. melanocarpus is found from North Carolina south to Florida and west to Arizona. It thought to be naturalized from the Old World, and is widespread in the Old World and New World tropics and subtropics. It grows along sandy roadsides and in disturbed areas.^[2] It is known to persist through repeated disturbance from prescribed fire.^[3]