Setaria palmeri

HABIT Perennial. Culms erect; 30–60 cm long. Leaf-sheaths glabrous on surface; outer margin glabrous. Ligule a fringe of hairs; 0.5–1 mm long. Leaf-blades 10–26 cm long; 6–12 mm wide; stiff. Leaf-blade midrib prominent beneath. Leaf-blade surface smooth, or scaberulous; rough on both sides. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle; exserted, or embraced at base by subtending leaf. Peduncle pubescent above.

Panicle spiciform; linear; loose; 5–20 cm long. Primary panicle branches 0.3–10 cm long; sterile at the tips. Panicle axis angular; pubescent, or villous.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1 in the cluster. Involucre composed of bristles; 3–10 mm long. Involucral bristles persistent; 1 per spikelet; flexible; antrorsely scaberulous; glabrous. Pedicels oblong.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 2–2.5 mm long; falling entire.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.5 length of spikelet; membranous; without keels; 3 -veined. Lower glume apex acute; mucronate. Upper glume ovate; 0.5–0.66 length of spikelet; membranous; without keels; 5–7 -veined. Upper glume apex acute; mucronate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 5 -veined; sulcate; acute. Palea of lower sterile floret 0.66 length of lemma. Fertile lemma ovate; dorsally compressed; gibbous; 2–2.5 mm long; indurate; without keel. Lemma surface rugose. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate.

DISTRIBUTION North America: Mexico.

NOTES Paniceae. Rominger 1994.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.