Pycnanthemum Michaux. Mountain-mint, Wild-basil.
A genus of 20-25 species, herbs, of temperate North America. Pycnanthemum remains a complicated and difficult group, with speciation apparently having proceeded by allopolyploidy, autoploidy, and aneuploidy. Numerous aberrant forms and (probably) sterile hybrids complicate identification and understanding.
Ref: Chambers (1993); Chambers & Hamer (1992); Grant & Epling (1943); Harley et al. In Kadereit (2004). Show full citations.
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