History and Impact
A native to Eurasia, rush skeletonweed currently infests several millions of acres of rangeland, cropland, rights of way and waste areas in eastern Washington (thus the efforts to keep it out of King County). Competing for water and nitrogen, it can severely reduce crop yield and forage for livestock and wildlife, and its wiry branches interfere with harvest. As a Class B noxious weed, its control is required in King County.

Biology and Morphology
Rush skeletonweed is a perennial with many branched, wiry stems that range from 1 to 4 feet tall. The rosette leaves resemble common dandelion and are hairless with deep, irregular teeth that point back toward the leaf base; they wither by flowering time. The plant has milky juice; coarse, reddish downward-pointing hairs at the base of the single flowering stem; and small yellow flowers and plumed seeds that ride the wind. It thrives in well-drained sandy or gravelly soils and has invaded extensive areas of shallow silt loam soils in other areas as well. In addition to deep (8+ feet) taproots, it has lateral roots that produce daughter rosettes. Plants also grow from buds on root fragments cut by cultivation or other equipment.

For more information about rush skeletonweed, please follow this link to the WA State Noxious Weed Control Board.

If you find rush skeletonweed in King County, please notify us through our online infestation form.

To find out where we have records of this weed in King County, use our interactive noxious weed map and search for rush skeletonweed.