General:
Perennial grass from fibrous roots and rhizomes; stems 60-150 cm tall, smooth, with 3 to 8 nodes, often branching above.

Leaves:
Sheath summits smooth to strongly hairy; leaf blades lax, usually flat, rough on both surfaces, often glaucous above, 5-30 cm long, mostly 3-8 mm wide; ligules mostly 3-8 mm long, with jagged margins.

Flowers:
Inforescence an open, lax or sometimes narrow panicle 10-25 cm long, the longer branches 3-8 cm long, sparsely- to densely-flowered on the upper 1/2; spikelets 1-flowered; glumes usually purple-tinged, thin, translucent along the margins, sharp- to long-pointed, usually rough, often bristly on the keels; lemmas thin, 2.5-4.5 mm long, with delicate, straight awns attached just below the middle and extending to or just beyond the tips, the callus hairs copious, mostly of uniform length, about as long as the lemmas; paleas thin, 1/2 to almost as long as the lemmas; rachillas short, inconspicuous, sparsely bearded with long hairs.

Notes:
Two intergrading varieties are recognized in BC and delimitation of each is arbitrary. Variety langsdorfii also intergrades with C. lapponica. The two varieties may be separated as follows:

1. Glumes 3-4 mm long, inconspicuously rough and thin, the keels lacking bristlelike hairs, translucent on the margins; awns thin, not prominent.................... var. canadensis

1. Glumes 4-6 mm long, conspicuously rough, the keels with bristlelike hairs, usually not translucent on the margins; awns thick, more prominent.................. var. langsdorfii (Link) Inman

Source:  The Illustrated Flora of British Columbia

Synonyms and Alternate Names:
Calamagrostis lactea Beal (pro sp.) [not hybrid]
Calamagrostis canadensis subsp. langsdorfii
Calamagrostis langsdorfii (Link) Trin.
Calamagrostis scabra