Bidens hyperborea

Bidens hyperborea (common names estuary beggarticks, northern beggar-ticks or estuary bur-marigold) is a coastal species of flowering plant in the daisy family. It grows along the coasts of Hudson Bay, the Arctic Ocean, and the North Atlantic Ocean in eastern Canada (Labrador, Nunavut, Ontario, Quebec, New Brunswick, Nova Scotia) and the northeastern United States (Maine, New Hampshire, Massachusetts, New York).
"Bidens hyperborea" is an annual herb up to 70 cm (28 inches) tall. It produces yellow flower heads sometimes one at a time, sometimes 2 or 3, each containing both disc florets and (usually) ray florets. The species grows in salt marshes and along the banks of marine estuaries.