Publication: New Flora and Botany of North America. 1: 57. 1836.
Origin: Native
selected vouchers: WS
Notes: Known only from a single, historic collection with no habitat data from Spokane Co. Additional specimens are needed to demonstrate that this species is established in the flora. Taxonomy follows FNA, distinguishing North American and Eurasian taxa at the species level. They differ in their chromosome level, fertility, and leaf venation.
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