2. Panicum anceps Michx. var. anceps (beaked panic grass)

Pl. 169 a, b; Map 663

Plants perennial, with long‑creeping rhizomes, forming clumps. Flowering stems 30–100 cm long, 3–6 mm in diameter below the middle, relatively stout and stiff, flattened toward the base, glabrous or somewhat roughened. Leaves scattered along the stems. Leaf sheaths rounded or keeled on the back, glabrous or hairy, the ligule 0.1–0.5 mm long, a short membrane. Leaf blades 10–50 cm long, 5–12 mm wide, firm, arched or spreading, glabrous or hairy, the margins sometimes inrolled, the midvein prominent and raised on the undersurface. Inflorescences 10–40 cm long, with the primary branches ascending to spreading, not spikelike, rebranched 1 or more times, the ultimate branches appearing somewhat 1‑sided, the spikelets oriented more or less in 2 rows, obliquely curved or turned at an angle from their short stalks. Spikelets 2.2–3.9 mm long, narrowly elliptic‑ovate in outline, sharply pointed at the tip, glabrous. Lower glume 1–2 mm long, 1/3–1/2 as long as the rest of the spikelet, ovate, bluntly to sharply pointed at the tip, 3‑ or 5‑nerved. Upper glume 2.2–3.9 mm long, narrowly elliptic‑ovate, sharply pointed at the tip, strongly 5‑ or 7‑nerved. Lowermost floret usually sterile and with a well‑developed but not hardened palea, the lemma 2.2–3.9 mm long, narrowly elliptic‑ovate, 5‑nerved. Fertile floret 1.4–2.9 mm long, narrowly oblong‑elliptic, bluntly pointed at the tip. Anthers 0.7–1.0 mm long. 2n=18, 36. June–October.

Scattered south of the Missouri River (New Jersey to Kansas south to Florida and Texas). Openings of bottomland forest and mesic upland forests, bottomland prairies, banks of streams, swamps, and fens; also ditches and wet, disturbed areas.

Another variety, var. rhizomatum (Hitchc. & Chase) Fernald, is restricted to the Atlantic and Gulf Coastal Plains. It differs in its slightly larger spikelets and more slender rhizomes.