County LogoClallam County, Washington

Olympic Knotweed Working Group

The Olympic Knotweed Working Group (OKWG) is a loose-knit consortium of about 20 government agencies, tribes, non-profits and private landowners, all working to eliminate invasive knotweed from waterways on the Olympic Peninsula.  The group has met twice a year since 2005, to share information and work together to control knotweed.  Clallam County Noxious Weed Control Board (CCNWCB), as the unofficial group leader, coordinates the meetings and supports the work of other group members. 

Meetings are usually held in the spring and fall and minutes are kept and sent out to interested parties. OKWG members give reports on their activities and experts in the field are invited to present at our meetings.  Most of the presentations from the last five years can be viewed here.  The attendees of the most recent meeting, together with their contact information can be seen by following the link.  We also put out a report each year. 

OKWG members have worked in all the major rivers on the Olympic Peninsula, and knotweed populations on most Clallam County rivers have been reduced by 90%!  However, it is important to keep monitoring and controlling the few plants that do appear, otherwise plants will spread and all our hard work will be undone.    

Map showing scope of work undertaken by OKWG partners on the Olympic Peninsula and neigboring counties

The map above shows the scope of work undertaken by OKWG partners, not just on the Olympic Peninsula but in neighboring counties also. The brown areas show where survey and treatment have taken place. The green dots represent knotweed found and/or treated in 2011. The map below shows the amount of knotweed observed on the Olympic Peninsula in 2015. Notice the notable reduction in the number of knotweed sites recorded from 2011 to 2015.

Olympic Peninsula Knotweed, 2015

Photo of crew member with knotweed
Crew member with knotweed
Photo of large knotweed patch after herbicide treatment
Large knotweed patch after herbicide treatment

The Hood Canal Coordinating Council is an active partner, which tracks knotweed control projects in the Hood Canal region and maintains records.  Follow the link to see the Habitat Work Schedule, which includes information on knotweed projects.  Follow this link for the Hood Canal Coordinating Council´s Regional Knotweed Control StrategyJefferson County´s Noxious Weed Control Program works closely with Clallam County in knotweed control.