Calamagrostis canadensis is a widespread and abundant, tall, perennial, caespitose grass found in a variety of habitats (usually in wet to moist situations) across Denali from the boreal lowlands into low alpine areas. Stems grow in tufts, arising from horizontal rhizomes, and can achieve heights of well over a meter (typically 50-150 cm). Stems have 3-8 nodes that often branch at the upper nodes. Leaf blades are typically flat, scabrous and 3-8 mm wide. The inflorescence is an open, often drooping panicle, 5-30 cm long, often purplish. Spikelets contain a single bisexual floret. The glumes are narrow. The lemmaawn is contained within the glumes, and the callus hairs are all of equal length, as long as the lemmas. Fruits are single-seed, indehiscent and dry. The key character for identifying this species from other Calamagrostis species is the length of the lemma hairs.
Calamagrostis canadensis greens up in early summer and produces flowers in mid to late summer.
Calamagrostis canadensis is monoecious, with stamens and pistils in the same florets (bisexual). Flowers are wind pollinated and seeds are wind disseminated. Seeds can reportedly remain viable up to 5 years in the soil. C. canadensis also extensively reproduces vegetatively by rhizomes.
C. canadensis has been used in streambank and shoreline restoration and stabilization projects.
Calamagrostis canadensis has a circumpolar, widespread distribution. It is occurs throughout North America, occurring widely in suitable habitat across all regions except is absent from the southeastern lower 48 states. In Alaska generally and Denali specifically, Calamagrostis canadensis is common and widespread occurring throughout the area in suitable habitats, although it is rarely abundant in the alpine zone.
Calamagrostis canadensis is the most common grass in Alaska occurring in a wide variety of habitats. Generally a low elevation species, it is found from 83 m to 1470 m with an average plot elevation of 585 m. It is most common on east, west, and south facing slopes. Although it is found in plots with slopes from 0 to 42 degrees, it prefers lower angled slopes with an average plot slope of 8 degrees.