Publication: Sp. Pl. 2: 904. 1753.

Origin: Native and introduced populations in Washington

Herbarium search: CPNWH

Notes: FNA21: "Helianthus annuus is widely distributed, including weedy, cultivated, and escaped plants. It is the only native North American species to become a major agronomic crop. Despite its considerable variability, attempts have failed to produce a widely adopted infraspecific system of classification. Forms with red-colored ray laminae, known from cultivation and occasionally seen escaped, trace their ancestry to a single original mutant plant. It hybridizes with many of the other annual species."

References:

Last updated 10/12/2020 by David Giblin.