Ox-eye sunflower, False sunflower (Heliopsis helianthoides).
Ox-eye is a clump-forming, upright, Missouri native perennial which occurs in open or rocky woods, thickets, prairies and along railroads throughout Missouri, except for the southeast lowlands. Heliopsis is both similar in appearance to and closely related to Helianthus, the true sunflower. Cold hardy to USDA zone 3-9.
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