General:
Perennial herb from a branched creeping rhizome; stems stout, erect or ascending, several, branched, moderately or more usually long-hairy with flattened hairs, sometimes reddish, 20-60 cm tall.
Leaves:
Basal leaves well-developed and larger than the stem leaves or reduced or lacking, rather thick with an expanded, clasping base, 2-3 times pinnately cut, the ultimate segments with indistinctly winged axis of the inflorescence and blunt or rounded tips; stem leaves similar, smaller, alternate, 5-20 cm long, 2-5 cm wide.
Flowers:
Heads with ray and disk flowers, several, terminal on the branches in a short, flat-topped inflorescence; involucres 4-6 mm tall; involucral bracts lanceolate to oblong, firm except for the papery margins and tip; ray flowers yellow, few; disk flowers yellow, 5-toothed, glandular.
Fruits:
Achenes squared off at the top, 5-angled, ribbed, glandular-dotted; pappus a minute, somewhat lobed crown.
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
Synonyms and Alternate Names:
Chrysanthemum bipinnatum subsp. huronense (Nutt.) HultΘn
Tanacetum douglasii
Tanacetum huronense Nutt.
Tanacetum huronense subsp. huronense
Tanacetum huronense var. bifarium Fern.
Tanacetum huronense var. floccosum Raup
Tanacetum huronense var. johannense Fern.
Tanacetum huronense var. terrae-novae Fern.
1. Heads disciform, numerous, usually 20-200.......................T. vulgare
1. Heads with ray and disk flowers, few to many, usually less than 20 2. Rays flowers white; leaves once or twice pinnately divided, the relatively broad segments often overlapping.......................T. parthenium 2. Rays flowers yellow; leaves twice to three times pinnately divided, the segments not at all overlapping........................T. bipinnatum Source: Illustrated Flora of British Columbia |