Dryas drummondii Richards. ex Hook.

Dryas drummondii Richards.; Hook. Bot. Mag. pL 2972. 1830
Dryas octopetala Drummondii S. Wats. Bibl. Tnd. 281. 1878. Dryadea Drummondii Kuntze, Rev. Gen. 215. 1891.
Perennial, with a cespitose, decumbent caudex; petioles 1-3 cm. long; blades elliptic or obovate, 1-3 cm. long, white-tomentose beneath, dark-green, dull, slightly tomentose or glabrous above, veiny and somewhat rugose, coarsely crenate, usually acute at the base and 401
rounded at the apex; scape 5-20 cm. long, tomentose and somewhat black-hairy above; hypanthium and calyx densely pubescent with black glandular hairs and slightly tomentose; petals yellow, about 1 cm. long, elliptic-spatulate or obovate, strongly ascending, almost erect; styles 3-4 cm. long in fruit, whiteor yellowish-plumose.
Type locality: [Canadian] Rocky Mountains.
Distribution: Eastern Quebec to Montana, Oregon, Southern Alaska, and Mackenzie.

Dryas drummondii is a species of flowering plant in the rose family known by the common names yellow mountain-avens, yellow dryas, or yellow dryad. It is native to Alaska, Canada, and northern states in the contiguous United States. This species is actinorhizal, able to live in symbiosis with nitrogen-fixing bacteria.