Description from Flora of China
Herbs, perennial, sometimes annual or biennial, or sometimes subshrubs. Leaves alternate, margin entire, serrate, or lobed. Capitula radiate, sometimes disciform or rarely discoid, solitary or several, sometimes numerous, in racemiform, corymbiform, or paniculiform synflorescences. Involucre hemispheric to campanulate or turbinate to cylindric; phyllaries 2-5-seriate, subequal, sometimes outer ones shorter, sometimes ± imbricate, linear-lanceolate to linear, membranous or herbaceous, margin scarious, midvein reddish brown, purplish, or green. Receptacles flat to slightly convex or conic, ± alveolate, naked. Ray florets fertile, rarely absent (discoid capitula) or 12-350, 1-5- or more seriate, inner series lamina reduced and/or elaminate, or all reduced or elaminate (disciform capitula), lamina purple, blue, pink, or white, rarely yellow or orange, usually short and narrow, sometimes ± broad; disk florets bisexual, 3-450, yellow (veins often orange), sometimes white, limb cylindric to narrowly funnelform [rarely campanulate], lobes (4 or)5, deltate; anther base obtuse, apical appendages ovate-lanceolate; style branch tips deltate, obtuse or arcuate. Achenes oblong or oblong-lanceoloid to oblong-obovoid, compressed to flattened, glabrous or sparsely to densely strigose or strigillose to sericeous, eglandular, 2(or 4)-veined, veins often orange. Pappus persistent or caducous, free or ± basally connate, 1- or 2-seriate, outer series of short setae or scales, inner of 5-40(-50) fine, barbellate or barbellulate bristles, sometimes pappus only on ray or only on disk achenes [or absent].
The sections of Erigeron used here follow Nesom (Lundellia 11: 8-38. 2008), except that the polyphyletic Conyza s.s. is included within the genus, as E. sect. Caenotus and E. sect. Conyza.
About 400 species: Asia, Europe, North America, a few in Africa and Australia; 39 species (14 endemic, six introduced) in China.
(Authors: Chen Yilin (陈艺林 Chen Yi-ling); Luc Brouillet)