General: Perennial, loosely tufted grass usually from rhizomes; stems 15-90 (120) cm tall, with visible nodes.
Leaves: Sheaths usually reddish, often shredding into fibres and often with hairs angled backwards, not persistent at the base of the stems; blades 6-30 cm long, 0.5-4 mm wide, folded or loosely folded; ligules 0.1-0.5 mm long.
Flowers: Inflorescence an open or loosely compact panicle, (2) 5-14 (20) cm long, the branches 1.5-8 cm long; spikelets (2-) 4- to 6- (10-) flowered, rarely with leafy bulbils in place of flowers, (6) 9-12 (13) mm long; lower glumes (2) 2.5-3.5 (4.5) mm long, the upper ones 3.5-5.5 (6) mm long; lemmas (4) 5-7 (8) mm long, awned, the awns (0.3) 1-3.3 (5) mm long; anthers (2.2) 3-4 (4.5) mm long; ovary tops smooth.
Notes: This polymorphic species complex is treated here as a single species for convenience, following Aiken and Darbyshire (1990) and Aiken (1993, 1994). Some distinctive native and introduced forms have been recognized as separate species or treated at infraspecific rank; however, numerous transitional forms occur between most of them (Pavlick 1985). Over 100 cultivated varieties of this complex are sold in Europe; some have been introduced into North America where hybridization with native forms further obscures the taxonomic picture. For an alternative treatment see Pavlick (1985), who recognized eight subspecies and two varieties for the complex in BC.
Wet to mesic beaches, tidal marshes, streambanks, meadows, gravelly sites and dry disturbed areas, roadsides and fields in the lowland to alpine zones; common in coastal and S BC, infrequent in N BC; circumpolar, N to AK, YT, NT, E to NF, and S to TN, NC, TX, NM and CA; Greenland, Iceland, Eurasia.
