Bidens polylepis

Bidens polylepis is a North American species of flowering plant in the family Asteraceae. It is native to south-central Canada and to the eastern and central United States.
Bidens polylepis is an annual herb up to 100 cm tall. It produces as many as 3 yellow flower heads per branch, each head containing both disc florets and ray florets. The species grows in marshes, flood plains, and disturbed sites.
Bidens polylepis is very closely related to Bidens aristosa, and they are known to intergrade over a broad geographic range. Because of this, they have been combined as a single entity by some authors.