Bristly foxtail (corn grass, Mary grass)
HABITAnnual; caespitose. Culms 10–150 (–200) cm long; without nodal roots, or rooting from lower nodes. Ligule a fringe of hairs. Leaf-blades linear, or lanceolate; plicate; 5–30 cm long; 5–20 (–30) mm wide; dark green.
INFLORESCENCE Inflorescence a panicle.
Panicle open; elliptic; 3–25 cm long; contracted about primary branches. Primary panicle branches bearing spikelets almost to the base; sterile at the tips. Panicle branches pubescent, or pilose.
Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1 in the cluster. Involucre composed of bristles; 1–15 mm long. Involucral bristles persistent; 1 in principal whorl; flexible; antrorsely scaberulous; glabrous.
FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; compressed slightly; 2–3.2 mm long; falling entire.
GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.25–0.33 length of spikelet; membranous; without keels; 3–5 -veined. Lower glume apex obtuse. Upper glume elliptic; 0.66–0.8 length of spikelet; membranous; without keels; 5–9 -veined. Upper glume apex obtuse.
FLORETS Basal sterile florets male, or barren; with palea. Lemma of lower sterile floret oblong; 1 length of spikelet; membranous; 7 -veined; without grooves, or sulcate; obtuse. Fertile lemma ovate; dorsally compressed; gibbous; 2–3 mm long; indurate; without keel. Lemma surface rugose. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate. Palea surface rugose.