Description: Mostly perennial herbs, rosette-forming or with branched leafy stems, some with rhizomes.
Leaves simple, alternate, margins entire to toothed.
Inflorescence terminal; heads pedunculate, solitary or in leafy corymbs or panicles, radiate. Heads campanulate, becoming reflexed; involucral bracts ± herbaceous, unequal, imbricate in 2–several series; receptacle naked, pitted, flat to convex. Ray florets fertile, 1- or 2-seriate, rays conspicuous, oblong, white to purple. Disc florets tubular, bisexual, yellow. Anthers obtuse at the base. Style branches flattened; with short, triangular, hirsute, terminal appendages.
Achenes compressed, often ridged, glabrous or hairy; pappus of numerous minutely barbellate bristles in 1 row, sometimes with an outer row of short hairs or scales.
Distribution and occurrence: World: c. 250 species, widespread in temperate America, Eurasia & Africa. Australia: 2 species (naturalized), Qld, Vic., S.A., W.A.
Text by M. F. Porteners Taxon concept:
| Key to the species | |
1 | Heads 2–4 mm diam.; leaves less than 11 mm wide, up to 15 cm long, margins entire; rays white, pink or blue | Aster subulatus |
| Heads 5–7 mm diam.; leaves more than 11 mm wide, 6–8 cm long, margins usually with a few small teeth; rays blue to purple | Aster novi-belgii |
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