Easily-confused!
If your specimen is/has a:with stems/​leaves ar­ranged:and the leaves:then you have:
☙ herbaceous,
vertical stem interior=​hollow, cham­bered with periodic diaphragms like bamboo
╟ alternate are ♤ heart-shaped except for a __ flat-base lookalike Japanese knotweed  Fallopia japonica.
woody stem (tree) are ♤ heart-shaped with a ∪ rounded-base lookalike eastern redbud  Cercis canadensis.
╫ opposite lookalike northern or hardy catalpa  Catalpa speciosa.
taper at both ends, and
pass the dogwood leaf test
this plant, please continue below …

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Learn more about ❀ flowering dogwood Cornus florida

🔍︎ 🔍︎ images Discover Life Encyclopedia of Life Michigan Flora Missouri Botanical Garden Missouri Plants Flora of North America NRCS PLANTS db USFS Wikipedia