Calamagrostis canadensis is a perennial C3 grass (Reich et al. 2003), to 1.5 m tall, aggressively colonial from rhizomes, stems clumped, often branched above, hairless.
Leaves alternate, blades 0.4- 0.8 cm wide, rough on both sides, flat; ligules 0.3-0.8 cm long;
Flower spikelets one-flowered, 0.2-0.6 cm long, jointed above glumes (glumes remain on inflorescence); glumes almost equal, lemma membranous, tip toothed, long-hairy at base, hairs about as long as lemma, awn arising from back of lemma; inflorescence dark gray to greenish, branched, open to somewhat dense, 8-25 cm long, often nodding, branches 3-8 cm long; blooms and fruits June-Aug.
Wetland status: FACW+.
Frequency in NYC: Apparently very infrequent.
Habitat: Open, wet sites.
Notes: Often planted in wetland restorations.