Michael Shephard, USDA Forest Service, Bugwood.org

Orange Hawkweed (Hieracium aurantiacum)

Perennial forb containing milky juice. Orange to red ray flower with notched tips clustered at the top of a leafless stem. Stems are erect with stiff hairs approximately 1.3-1.2m tall. Leaves are mostly at the base and are spatulate-shaped covered in hairs. It has a fibrous root system and above ground stolons. The seeds are a dandylion-like plume.

Habitat and Ecology

In BC, Orange Hawkweed grows from low to mid elevations and is well –adapted to well-drained soils that are often acidic. It is found in pastures, cutblocks, meadows, clearings and both disturbed and undisturbed sites.

Impacts

Populations can expand quickly by the vegetative growth of the stolons and establish dense mats of rosettes. Orange Hawkweed can, and will, invade native ecosystems. It disperses by three methods, seeds, roots and stolons making it particularly aggressive.

Management

Small populations can be hand-pulled but ensure proper disposal and containment of roots and stolons. Mowing can decrease the seed but this may increase the vegetative growth of the roots and stolons. Chemicals provide excellent control when applied in spring and early summer (refer to the Guide to Weeds in BC for more information).

References

Province of British Columbia. 2002. Guide to Weeds in British Columbia.

http://www.agf.gov.bc.ca/cropprot/fieldcrop/index.htm