This aggressive invader from Europe is also known as devil's paintbrush. It outcompetes many native species by forming dense, monotypic stands, or competes with forest understory plants.
Legal status in King County, Washington
Class B noxious weed. Property owners in King County are required to control this plant. This species is also on the Washington quarantine list (known as the prohibited plants list) (external link) and it is prohibited to transport, buy, sell, offer for sale, or to distribute plants or plant parts, seeds in packets, blends or "wildflower mixes" of this species, into or within the state of Washington.
Biology and morphology
Easily recognized by its showy red-orange flowers, it is a perennial with lance-shaped, hairy leaves that form a basal rosette. The erect, bristly stem grows up to twelve inches tall, producing 5 to 30 flowers at the tip. Occasionally there are one or two small leaves on the stem. The entire plant contains a milky juice. The root system is fibrous.
After starting to flower, each plant produces several white-fuzzy stolons that extend 4 to 12 inches and form the next generation of plants. It thrives in disturbed areas such as roadsides, gravel pits and pastures. It can also invade meadows and forested areas and is well-adapted to life at higher eleventations. Usually found in sunny areas, it is somewhat shade tolerant. It spreads by seeds, stolons and rhizomes.
Additional information on orange hawkweed
What to do if you find this plant in King County, Washington
Please notify us if you see orange hawkweed growing in King County. Our program staff can provide the property owner or appropriate public agency with site-specific advice on how best to remove it. We map all known locations of regulated noxious weeds such as orange hawkweed in order to help us and others locate new infestations in time to control them.