erect perennial strong-scented with serrate pointed leaves and a loose panicle of yellowish flowers; the eastern United States
[ Syn: horse balm , stoneroot , stone-root , richweed , stone root , collinsonia canadensis ]
common North American weed with linear leaves and small discoid heads of yellowish flowers; widely naturalized throughout temperate regions; sometimes placed in genus Erigeron
[ Syn: canadian fleabane , fleabane , conyza canadensis , erigeron canadensis ]