Perennials; rhizomatous. Stems usually simple, sometimes ± branched. Heads radiate. Ray florets fewer than disc florets, in 1 series (corollas conspicuous). Disc corollas ± ampliate, lobes usually erect, sometimes spreading or reflexed. Pappi shorter than to equaling disc florets at flowering. x = 8.

Distribution

North America, Mexico, widely introduced worldwide through ornamental horticulture.

Discussion

Species 39+ (36 in the flora).

Subsections have been recognized within sect. Symphyotrichum. They are not treated formally here. Subsectional phylogeny is mostly unresolved. Lists of species (from the flora area) within each subsection are provided here as a rough guide to relationships.

Subsection Heterophylli (Nees) Semple: Symphyotrichum cordifolium, S. ciliolatum, S. drummondii, S. anomalum, S. shortii, S. undulatum, S. urophyllum, S. oolentangiense, S. laeve, S. retroflexum.

Subsection Porteriana (Rydberg) G. L. Nesom: Symphyotrichum depauperatum, S. parviceps, S. pilosum, S. porteri, S. priceae.

Subsection Dumosi (Torrey & A. Gray) G. L. Nesom: Symphyotrichum dumosum, S. simmondsii, S. racemosum, S. eulae, S. tradescantii, S. lateriflorum, S. ontarionis, S. lanceolatum, S. praealtum, S. boreale, S. nahanniense, S. welshii.

Subsection Symphyotrichum: Symphyotrichum elliottii, S. puniceum, S. firmum, S. rhiannon, S. prenanthoides, S. novi-belgii, S. anticostense, S. robynsianum.

Undeteremined [often treated as monotypic sect. Turbinelli (Rydberg) Semple]: Symphyotrichum turbinellum.

Selected References

None.

Lower Taxa

Symphyotrichum anomalum, Symphyotrichum anticostense, Symphyotrichum boreale, Symphyotrichum ciliolatum, Symphyotrichum cordifolium, Symphyotrichum depauperatum, Symphyotrichum drummondii, Symphyotrichum dumosum, Symphyotrichum elliottii, Symphyotrichum eulae, Symphyotrichum firmum, Symphyotrichum laeve, Symphyotrichum lanceolatum, Symphyotrichum lateriflorum, Symphyotrichum nahanniense, Symphyotrichum novi-belgii, Symphyotrichum ontarionis, Symphyotrichum oolentangiense, Symphyotrichum parviceps, Symphyotrichum pilosum, Symphyotrichum porteri, Symphyotrichum praealtum, Symphyotrichum prenanthoides, Symphyotrichum priceae, Symphyotrichum puniceum, Symphyotrichum racemosum, Symphyotrichum retroflexum, Symphyotrichum rhiannon, Symphyotrichum robynsianum, Symphyotrichum shortii, Symphyotrichum simmondsii, Symphyotrichum tradescantii, Symphyotrichum turbinellum, Symphyotrichum undulatum, Symphyotrichum urophyllum, Symphyotrichum welshii