E-Flora BC: Electronic Atlas of the Flora of British Columbia

General:
Perennial herb from a rhizome; stems erect, numerous, branched, 1-3 m tall, reddish-brown.

Leaves:
Basal leaves lacking; stem leaves alternate, 10-15 cm long, the blades egg-shaped to more or less round, the bases rounded or squared off, the tips abruptly pointed, long stalked; stipules short, tubular, entire, usually deciduous.

Flowers:
Inflorescence of numerous flowers in many panicles; perianths whitish or greenish-white, about 2 mm long at anthesis, 5-lobed nearly to the base.

Fruits:
Achenes, 3-angled, black, smooth and shiny, 2.5-3 mm long.

Notes:
Easily confused with P. sachalinense.