17. Panicum malacophyllum Nash

Pl. 165 c, d; Map 678

Dichanthelium malacophyllum (Nash) Gould

Plants perennial, without rhizomes, forming tufts. Flowering stems 20–60(–70) cm long, erect or spreading, initially unbranched, becoming much‑branched during the summer and autumn, the nodes densely bearded with relatively long, spreading to downwardly pointed hairs, the internodes pubescent with shorter, soft, gray, velvety hairs. Foliage in a dense rosette of shorter, somewhat broader leaves at the base and longer, narrower leaves well distributed along the main stems, those of the later branches even shorter and narrower. Leaf sheaths pubescent with soft, gray hairs, the ligule 0.6–1.5 mm long, an inconspicuous line or band of hairs. Leaf blades of the main stems 3–10 cm long, 4–12 mm wide, narrowed toward the base, relatively thick and stiff, usually densely pubescent on both surfaces with soft, gray, velvety hairs, the margins with scattered short to long hairs near the base, dull green to dark green. Inflorescences 3–9 cm long, the earlier ones larger and more open with mostly spreading to loosely ascending branches (later ones sometimes reduced to small clusters of long‑stalked spikelets), the branches mostly rebranched 1 or more times, not spikelike or 1‑sided, pubescent with conspicuous, spreading hairs, the spikelets appearing mostly long‑stalked at the tips of the branches. Spikelets 2.3–3.2 mm long, elliptic‑obovate in outline. Lower glume 0.8–1.1 mm long, mostly about 1/3 as long as the spikelet, broadly ovate, sharply pointed at the tip, glabrous or sparsely hairy, nerveless or faintly 1–5‑nerved. Upper glume 2.2–3.2 mm long, elliptic‑obovate, rounded or very bluntly pointed at the tip, 5–9‑nerved, hairy, the hairs mostly with pustular bases. Lowermost floret sterile and with a reduced, inconspicuous palea, the lemma 2.2–3.2 mm long, elliptic‑obovate, rounded or very bluntly pointed at the tip, 5–9‑nerved, hairy, the hairs mostly with pustular bases. Fertile floret 1.8–2.4 mm long, elliptic, rounded or bluntly pointed at the tip. Anthers 0.2–0.9 mm long. May–July (vernal), July–September (autumnal).

Scattered in the Unglaciated Plains Division and western portion of the Ozarks, uncommon farther north and east (Missouri and Kansas south to Tennessee, Arkansas, Oklahoma, and Texas). Upland prairies, sand prairies, glades, banks of intermittent streams, margins of ponds and alkaline seeps, and mesic to dry upland forests, often on acidic substrates; also roadsides and old fields.