Cirsium P. Miller. Thistle.
A genus of about 250 species, herbs, north temperate.
Key adapted in part from Cronquist (1980); portions of key based on Keil (2006f).
Ref: Cronquist (1980); Keil (2006f) In Flora of North America Editorial Committee (2006a); Nesom (2021i); Nesom (2022a). Show full citations.
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