widespread rank-smelling weed having white-rayed flower heads with yellow discs

(Matricaria) A common difficult to control daisy like weed.

Matricaria is a genus of flowering plants in the sunflower family (Asteraceae). Some of the species have the common name of "mayweed," but this name also relates to plants not in this genus.

The feverfew.

A composite plant (Anthemis Cotula), having a strong odor; dog's fennel. It is a native of Europe, now common by the roadsides in the United States.