Bidens hyperborea

About

Bidens hyperborea is a species of flowering plant in the family Asteraceae commonly known as estuary beggarticks, northern beggarticks, or estuary bur-marigold. Known from marshes and estuarine regions in northeastern North America, it is a variable annual herb with yellow flowers similar to Bidens cernua, Bidens laevis, and Bidens eatonii. B. hyperborea is listed as an endangered species in the state of Massachusetts, where it is threatened by habitat degradation, and is listed by NatureServe as critically imperiled (S1) in the province of Ontario and possibly extirpated from New Hampshire.

Summary from Wikipedia