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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

Biological Controls

Biological control is a term used when living organisms are used to control weeds. Beetles or weevils are used as biocontrols, but so are moth larvae, goats and even fungi or rusts. Biological controls can control the target weed directly or indirectly, but they will cinnabar moth caterpillar on tansy ragwortnot eradicate the plant population from a site. Weeds are directly impacted when the biocontrols destroy plant parts that prevent growth, or prevent seed production. Biocontrols also impact a weed indirectly when the stressed plants are no longer able to out compete native or beneficial plants on a site.

It can take 4 to 5 years for any visible signs of weed control, making this an effective tool in a long-term control plan. Releasing biological control agents is an option on sites with large stands of weeds, when immediate control is not possible. For more information on biological control research, please follow the links.

The King County Noxious Weed Program is part of a statewide network using biological control agents. We work closely with federal, state and county agencies. A new position was created within WSU Cooperative Extension, King County, to help coordinate the biological control activities of noxious weed programs throughout western Washington.

Biological control photos - click thumbnail for larger image

caterpillar larve - click for larger image Olivia the goat - click for larger image cinnabar moth on leaf - click for larger image Galerucella beetle - click for larger image St. Johnswort beetles - click for larger image

For more information, contact:

Jennifer Andreas, WSU Extension - click for contact informationJennifer Andreas
Integrated Weed Control Project
Washington State University Extension
WSU Puyallup Research and Extension Center
2606 W Pioneer
Puyallup WA 98371-4900

253.445.4657 office
253.651.2197 cell
253.445.4571 fax
jandreas@wsu.edu

Related Information

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.