Sporobolus compositus var. compositus

General:
Perennial, strongly tufted grass from fibrous roots; stems nearly or quite solid, longitudinally grooved, smooth, usually 60-100 cm tall.

Leaves:
Sheaths open, smooth or soft-hairy; blades usually in-rolled, tough, 1-4 mm wide, mostly soft-hairy above, especially near the ligules, the collars smooth or slightly hairy near the margins; ligules scarcely 0.5 mm long.

Flowers:
Inflorescence a narrow, spikelike panicle, up to 15 cm long, usually at least partially enclosed in the sheath, the branches erect; spikelets 1-flowered, strongly flattened; glumes blunt, the lower ones 2.5-3 mm long, the upper ones about 1 mm longer; lemmas blunt, smooth, 4-5 mm long, paleas nearly equal to the lemmas; lodicules fan-shaped, about 0.5 mm long; anthers 1.5-2.5 mm long.

Source:  The Illustrated Flora of British Columbia