Common burdock
(Arctium minus)
Common burdock is an introduced biennial which reproduces by seed. In the first year of growth the plant forms a rosette. The second year the plant grows erect up to 6 feet tall. Burdock has enormous leaves and a prickly bur. The flowers are purple and white in numerous heads. Burdock grows along roadsides, ditch banks, and neglected areas.
This plant is a very serious threat to sheep as the burs can significantly damage the quality of their wool. Burdock will also cause eye infections in cattle. It is found in various locations throughout Garfield County.