Lachnagrostis palustris

Tufted, glabrous, perennial, 25–80 cm tall including inflorescences; culms erect but often strongly geniculate, sometimes branched; nodes mostly enclosed or just exserted beyond the leaf sheath; lower leaf sheaths usually strongly purpled. Leaf blades erect, smooth to scaberulous, generally involute when young but flattening with age, 5–15(–20) cm long and 0.2–1.5 mm wide; ligule membranous, acute, becoming lacerate, (4–)6–8 mm long. Inflorescence an open panicle, 10–35 cm long from the lowest whorl, exserted at maturity with erect, divaricate to spreading, primary branches to 8 cm long but often less than 5 cm long. Spikelets (3.2–)3.4–3.7(–4.0) mm long, strong purple but fading with age to pale golden-brown; glumes acuminate, unequal, the lower 0.2–0.4 mm longer, keels scabrous, lateral surfaces smooth to finely papillose, margins without or with a few scattered cilia; lemma acute, 1.5–1.8 mm long, minutely 4–toothed at the apex or sometimes the lateral nerves extended into short setae (0.5–0.7 mm), covered in 0.3–0.5 mm long hairs, callus with hairs 0.5–0.7 mm long; awn inserted at near the mid-dorsal region of the lemma, (4.3–)5.0–6.0(–6.5) mm long, strongly geniculate, the bristle 1.5–2.0 times as long as the column; palea 1.2–1.6 mm long; rachilla extension plumose, 1.2–1.6 mm long including hairs; anthers 0.4–0.5(–0.6) mm long. Flowers/fruits Nov.–Feb.