Petasites Mill.
Dioecious perennial herbs. Lvs simple, palmately toothed, lobed or dissected, mostly basal; cauline lvs alternate, much reduced and scale- like. Capitula solitary or in corymbs or panicles; involucral bracts in 1-2 rows, with shorter supplementary bracts subtending base of involucre. Receptacle flat; scales 0. ♂ capitula with outer florets sterile, ligulate or filiform, and inner florets ♂, tubular. ♀ capitula with outer florets ♀, ligulate, filiform or tubular, and inner florets sterile, tubular. Ligules purple to pink or white. Achenes cylindric, ribbed, glabrous; pappus present.
18 spp., N. Hemisphere. Naturalised sp. 1.
This genus was revised by Toman, J., Folia Geobot. Phytotax. 7 : 381-406 (1972).
