Erigeron

Erigeron (/ɪˈrɪdʒərɒn/)[4] is a large genus of plants in the daisy family.[5] It is closely related to the genus Aster and the true daisy Bellis. The genus has a cosmopolitan distribution in dry, mountainous areas and grassland, with the highest diversity in North America.[5][6][7][8][9]

Its English name, fleabane, is shared with related plants in several other genera. It appears to be derived from a belief that the dried plants repelled fleas[10] or that the plants were poisonous to fleas.[11] The generic name Erigeron is derived from the Ancient Greek words ἦρι (êri) “early in the morning” and γέρων (gérōn) “old man”, a reference to the appearance of the white hairs of the fruit soon after flowering[12] or possibly alluding to the early appearance of the seed heads.[13] The noun γέρων is masculine,[14] so that specific epithets should have masculine endings (e.g. glaucus) to agree with it. However, authors have incorrectly used neuter endings (e.g. glaucum), because the ending -on resembles the ending of Ancient Greek neuter second declension nouns, as Augustin Pyramus de Candolle did in his 1836 account of the genus.[15]

The species may be annuals, biennials, or perennials. They are well-branched with erect stems, characterized by their numerous white, lavender, or pink ray flowers and yellow disc flowers. Some members of this group have no ray flowers. The pappus (=modified calyx, forming a crown) is shorter than in Aster, and consists of bristles. The ray florets are narrower than in Aster, but are clearly longer than the involucre (=whorled bracts).