Holiday closure Monday May 28: Most county offices will be closed in observance of Memorial Day.

To offer a suggestion or report an error on the King County Noxious Weeds Web site, please contact Sasha Shaw, education specialist.
King County, Washington noxious weed identification and control

Purple starthistle
Centaurea calcitrapa

purple starthistle flowerThis Class A noxious weed has a limited distribution in Washington State; control and eventual eradication is required in King County. Purple starthistle invades pastures, meadows, and fields, displacing native and/or beneficial forage species.

Additional information on purple starthistle

What to do if you find this plant in King County, Washington

Please notify us if you see purple starthistle 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. Also, because purple starthistle is not established in King County, we have an opportunity to stop it from spreading if we act quickly. We map all known locations of regulated noxious weeds such as purple starthistle in order to help us and others locate new infestations in time to control them.

Purple starthistle photos - click thumbnail for larger image

purple starthistle plant - click for larger image purple starthistle rosette - click for larger image

Report purple starthistle in King County, Washington

Locate purple starthistle in King County, Washington

Related information

Related agencies

Program offices are located at 201 S. Jackson St., Suite 600, Seattle, WA 98104. To contact a staff member at the King County Noxious Weed Control Program, please call 206-296-0290 or by reach them by email.