Keys to Identification:

• Orange hawkweed is a perennial member of the sunflower family (Asteraceae)

• It likes moist grassy areas and can be found along creeks, in meadows, and along rights-of-way

• Reproduces by runners and by seed

• Each bright orange flower is between 1/2 to 1 inch wide.  They are grouped at the top of a slender stem and tend to close up when it is shady, making the plants difficult to see

• Hairy leaves are found at the base of the plant

• Orange hawkweed is found in only a few places in Colorado and is on the A List, requiring eradication

This information courtesy of the Colorado Natural Areas Program

Family: Asteraceae (Sunflower)

Other Names: Devil's paintbrush

USDA Code: HIAU

Legal Status: Colorado Noxious Weed List A

New in Colorado – Notify your county weed supervisor if you find this plant!

IDENTIFICATION

Lifecycle: Perennial

Growth form: Forb

Flower: Orange in groups of up to 13 at the end of stem

Seeds/Fruit: With papus

Leaves: Basal. Dark green hairy.

Stems: Fine, leafless.  1-2 feet tall. With stiff hairs

Roots: Fibrous spreading with stolons at nodes

Seedling: Seedling leaves have bristly hairs

SIMILAR SPECIES

Exotics: Yellow hawkweed

Natives: Native hawkweeds and false dandelion

IMPACTS

Agricultural: Infests hay fields, animals will not feed

Ecological: Forms mats that prevent other plants from growing

HABITAT AND DISTRIBUTION

General requirements: Likes shady areas.  Can be found in grassy areas. Moist pastures, stream banks

Distribution: Found in a number of counties in Colorado in small populations.  Native to Europe, also found throughout northern US

BIOLOGY/ECOLOGY

Life cycle: Perennial plants form rosettes in spring and early summer, spread primarily through stolons.  Plants flower in June-July  

Mode of reproduction: Seed, stolons, rhizomes

Seed production: Each stem may produce thousands of seeds

Seed bank: Not known

Dispersal: Wildflower seed mixes, wind, water and possibly animals 

REFERENCES

Callihan, R.H., L.M. Wilson, J.P. McCaffery, T.W. Miller, 1997. Hawkweeds.  Pacific Northwest Extension Publication 499.  Cooperatively published by the University of Idaho Cooperative Extension, Oregon State Cooperative Extension Service, Washington State Cooperative Extension and the U.S. Department of Agriculture.

Hoffman, R. & K. Kearns, Eds.. 1997. Wisconsin Manual of Control Recommendations for Ecologically Invasive Plants. Wisconsin Dept. Natural Resources. Madison, Wisconsin.. 102pp.

Whitson, T.D. (Ed.) et al.. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative Extension Services, University of Wyoming. Laramie, Wyoming. 630pp.