Family: Asteraceae |
Perennials, 15-60(-100) cm (taproots relatively massive; caudices seldom branched). Stems erect (or bending erect from bases), branched mostly from bases. Leaves basal and cauline; alternate; usually petiolate (basal), sometimes sessile; blades (usually pinnately nerved, basal larger than cauline) ± deltate, elliptic-ovate, lanceolate, lance-elliptic, lance-linear, or oblong-ovate, bases truncate to cuneate, margins usually entire, rarely dentate to serrate (sometimes ciliate), faces glabrous or hairy (sometimes gland-dotted or finely stipitate-glandular). Heads radiate, borne singly or 2-5(-8+) in ± corymbiform to racemiform arrays. Involucres hemispheric to campanulate or turbinate, 12-60+ mm diam. Phyllaries persistent, 12-36(-48) in 2-3+ series (subequal to unequal, outer sometimes foliaceous, much larger than inner). Receptacles flat to convex, paleate (paleae conduplicate, at least bases, papery). Ray florets 5-25+, pistillate, fertile; corollas mostly yellow (cream to white in W. helianthoides). Disc florets 35-150+, bisexual, fertile; corollas yellow, tubes much shorter than cylindric throats; lobes 5, ± deltate to lanceolate (style branches stigmatic in 2 barely distinct lines, appendages ± filiform). Cypselae ± prismatic, weakly 3-4-angled (faces glabrous or hairy); pappi 0, or persistent, coroniform (usually lacerate) or of 1-4+ ovate to subulate, erose to lacerate (often basally connate) scales. x = 19. Some species formerly included in Wyethia are here treated in Agnorhiza and Scabrethia. Balsamorhiza is closely related to Wyethia.
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