General:
Perennial, tufted grass from fibrous roots (sometimes flowering as a winter annual); stems erect or decumbent and freely rooting at the nodes (especially when growing in standing water), 20-70 cm tall.

Leaves:
Sheaths open; blades lax to firm, densely and minutely rough at least on the upper surfaces, (1) 2-5 mm wide; ligules jagged or entire, sharp-pointed but usually folded back, (2) 4-8 mm long.

Flowers:
Inflorescence a pale green, cylindrical panicle, mostly 1.5-7 (8) cm long; spikelets less than 4 mm long (excluding the awns); glumes (1.8) 2-2.3 (2.5) mm long, more or less silky over the back, the nerves fringed with long, fine hairs, tips rounded and somewhat wax-papery; lemmas with margins fused for slightly less than 1/2 their length, subequal to the glumes, awned, the awns inserted at or just below midlength, straight, about equal to or slightly longer than the glumes (exserted less than 1.5 mm beyond them), 2-3 mm long; anthers (0.5) 0.6-0.7 (1) mm long.

Source:  The Illustrated Flora of British Columbia