Synonyms for Dog Fennel (same or very similar meaning)
WordNet sense 1 (weedy plant of southeastern United States having divided leaves and long clusters of greenish flowers):
Eupatorium capillifoliumWordNet sense 2 (widespread rank-smelling weed having white-rayed flower heads with yellow discs):
mayweed, Anthemis cotula, stinking chamomile, stinking mayweedFrom the ODE community, based on WordNetadd/edit