Scientific Name: Conyza canadensis
Weed Family: Asteraceae


Horseweed is an annual weed, winter or summer, depending on location. Horseweed is an upright growing plant and can reach 4 - 5 feet if not mowed. Horseweed grows in a basal rosette. The leaves which are oblanceolate in shape are 3- to 4-inches in length. The leaves alternate and have margins that are toothed. The stem of horseweed is simple and unbranched, and covered with hair. Horseweed has a taproot. The inflorescence is a panicle of heads with pink to white flowers. Horseweed spreads by seed produced in the summer. Horseweed is found through out the United States.

Herbicide Use

Make your post-emergence herbicide application when horseweed is young and actively growing.


Germination Dates

Zone-3: MayZone-4: MayZone-5: MayZone-6: AprilZone-7: AprilZone-8: MarchZone-9: March