General: Perennial herb from a stout rhizome; stems erect, solitary, branched, glabrous to sparsely hairy, dotted with glands, 0.4-1.5 m tall.
Leaves: Basal leaves lacking; stem leaves alternate, 10-20 cm long, 4-8 cm wide, unstalked or short-stalked, pinnately cut, the axis of the inflorescence evidently winged, the ultimate segments again pinnately cut or deeply lobed and toothed.
Flowers: Heads disciform, numerous, terminal on the branches in a short, flat- to round-topped inflorescence; involucres 2-3 mm tall; involucral bracts lanceolate, in 2-3 series, keeled, firm except for the papery margin, hairy at the base; ray flowers lacking; marginal flowers glandular, 3-lobed; disk flowers yellow, 5-toothed into rounded lobes, sparsely glandular.
Fruits: Achenes squared off at top, 1 mm long, 5-angled, glandular-dotted; pappus a minute, narrow-toothed crown.
This species has become a common invader in southern British Columbia, often forming thick stands along roadsides and railway track verges. It is listed as one of the top fourteen species of concern by the Coastal Invasive Plant Committee, for more information visit their web site.
Ecology
Ecological Framework for Tanacetum vulgare
The table below shows the species-specific information calculated from original data (BEC database) provided by the BC Ministry of Forests and Range. (Updated August, 2013)
