Orange hawkweed (Hieracium aurantiacum)

Family: Asteraceae (Compositae)

Description and Variation:  Orange hawkweed has matted hairy leaves and handsome flowers, each about an inch in diameter and usually red on the margin, merging into an orange-colored center. The flowering branches, or shoots, grow from a few inches to two feet in height. They are leafless and covered with stiff black hairs.

Economic Importance:  Hawkweeds are aggressive competitors of pasture and range plant species. Orange hawkweed is unpalatable and thus crowds out more palatable species.

Geographic Distribution:  Orange hawkweed is widely distributed in northeastern Washington with the largest known population in Pend Oreille County. It is occasionally reported from western Washington.

Habitat: Orange hawkweed grows in permanent meadows, grasslands, rangelands, and pastures.

History:  Orange hawkweed was first introduced from Europe into New England because of its attractive flame-colored flowers. Originally it was a garden ornamental. This species was introduced to Spokane in 1945.

Growth and Development:  Orange hawkweed is a perennial plant.

Reproduction:  Orange hawkweed reproduces from seeds and stolons and/or rhizomes.

Response to Herbicides: 

Response to Cultural Methods:  In scattered patches of small size, the simplest mode of attack is to dig out the orange hawkweed plants. Make sure that all of the below-ground growth is also removed, since even a small piece if left in the soil may develop into a new plant. These plants   should be carried away and either burned or placed in a refuse pile where they can do no harm.

Rational for Listing:  H. aurantiacum is considered to be one of the most noxious weeds in the New England states, as reflected by common names such as King Devil and Devil’s Paintbrush. In our area Hitchcock and Cronquist reports it only as "West of the Cascades in Washington and in Flathead County Montana". Other sources however show H. aurantiacum to be widely distributed in northeastern Washington with the worst of the known infestations occurring in Pend Orielle County. A note by Marion Ownbey at the Washington State University herbarium shows this species to have been introduced in Spokane in 1945. H. aurantiacum is a serious pest of lowland pasture, mountain meadows, and lawns. It is often cosmopolitan (found in cities) because the unwary wildflower enthusiast has been known to bring it home as an ornamental.

References:

Callihan, R.H., C.C. Thill and D. W. Wattenbarger. Hawkweeds. Current Inf. Series no. 633. University of Idaho Cooperative Extension.

Hansen, Albert A. 1920. The Hawkweeds, or Paintbrushes. Circular 130. U.S.D.A.

Old, Rich. 1984. Plant Notes.