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orange hawkweed (Hieracium aurantiancum)
ODA rating: A
Other common names
Devil's paintbrush
Description
Orange hawkweed is a perennial weed with above-ground runners (stolons) that root at the tips. Roots are shallow and fibrous. The plant grows up to 12 inches tall and contains milky juice. The vibrant orange-red colored flowers are clustered at the top of a leafless stem. Stiff, black, glandular hairs cover flower stalks. Leaves are hairy, lance shaped, up to five inches long, and exclusively basal.
Impacts
Once established, hawkweed quickly develops into a patch that continues to expand until it covers the site with a solid mat of rosettes. A dense mat of hawkweed plants has the potential to eliminate other vegetation. It displaces native vegetation posing a serious threat to native plant communities and can dominate pastures, lawn and roadsides. It is unpalatable and crowds out more desirable species. This invader weed from Europe thrives in poor non cultivated and disturbed soils. Orange hawkweed occurs on native meadows, gravel pits, forest openings, permanent pastures, roadsides, and hayfields. It prefers well-drained, coarse textured soils that are moderately low in organic matter. Hawkweeds do not persist in cultivation.
Click on image to view larger image.
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Photo by Bonnie Rasmussen, Oregon Department of Agriculture
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Photo by Jim Schultz, Hines, Oregon
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Photo by Bonnie Rasmussen, Oregon Department of Agriculture
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If images are downloaded and used from the ODA web site please be sure to credit the photographer.
Introduction
Orange hawkweed is found from western Washington to Wyoming and is known to occur in eastern states. Due to its striking flowers, plant enthusiasts have assisted in the distribution of this weed.
Distribution in Oregon
In Oregon, distribution is limited to a few sites. One established population is known in Clackamas County and a few ornamental plantings have been reported and confirmed in Deschutes County.
Map legend
Yellow: limited distribution in county
Red: abundant in county
Grey: not known to be present in county
Biological controls
No approved biocontrol agent currently available for this weed. Orange hawkweed is an “A” listed noxious weed in Oregon, meaning that is very limited in distribution. All known infestations are under intensive management for eradication or containment.
Informational Links
WeedMapper
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