14. Panicum laxiflorum Lam.

Pl. 168 h–j; Map 675

Dichanthelium laxiflorum (Lam.) Gould

Plants perennial, without rhizomes, forming dense tufts. Flowering stems 10–50 cm long, erect or nearly so, unbranched or becoming branched only at the base during the summer and autumn, the nodes with a conspicuous beard of spreading to downward‑pointing hairs, the internodes glabrous. Foliage usually crowded toward the base of the plant (due to the very much shortened internodes toward the bases of the flowering stems), the leaves above the bases of the flowering stems usually few, about the same size or slightly shorter and narrower than the basal leaves, light green to yellowish green. Leaf sheaths long‑hairy, the ligule 0.2–0.5 mm long, a (sometimes minutely hairy) membrane along the margin. Leaf blades 7–15 cm long, (3–)5–12 mm wide, mostly 10–15 times as long as wide, erect or ascending, linear to narrowly lanceolate, narrowed or somewhat rounded at the base, relatively thin and soft, usually long‑hairy on the margins and surfaces. Inflorescences 4–12 cm long, the earlier ones larger than the later ones (these often hidden among the leaves), the branches spreading to loosely ascending, mostly rebranched 1 or more times, not spikelike or 1‑sided, the spikelets appearing mostly long‑stalked at the tips of the branches. Spikelets 1.7–2.3 mm long, elliptic to oblong‑obovate in outline. Lower glume 0.4–0.8 mm long, 1/4–1/3 as long as the spikelet, broadly ovate, rounded to bluntly pointed at the tip, usually hairy, nerveless or faintly 1–5‑nerved. Upper glume 1.5–2.3 mm long, elliptic, rounded or bluntly pointed at the tip and not extended past the fertile floret or beaked, strongly 7‑ or 9‑nerved, hairy. Lowermost floret usually sterile and with a reduced, inconspicuous palea, the lemma 1.5–2.3 mm long, elliptic, rounded or bluntly pointed at the tip and not extended past the fertile floret or beaked, strongly 7‑ or 9‑nerved, hairy. Fertile floret 1.3–2.1 mm long, oblong‑elliptic, rounded or with a short point at the tip. Anthers 0.3–1.5 mm long. 2n=18. May–August (vernal), July–October (autumnal).

Scattered in the Ozark, Ozark Border, and Mississippi Lowlands Divisions (southeastern U.S. west to Missouri and Texas; Mexico, Central America, Caribbean Islands). Bottomland forests, mesic to dry upland forests, glades, and banks of streams and rivers, mostly on acidic substrates and often in sandy soil; also roadsides and edges of trails.