How do you solve a problem like knotweed?

Coming together to tackle knotweed: A community forum

Oxbow Farm & Conservation Center is holding a series of tours and gatherings this summer to discuss invasive knotweed, its impacts, and ongoing investigations into chemical and manual control methods by Oxbow, King County, and partner organizations. If you’re a local farmer, landowner, or land manager and are looking for strategies and discussion about how to control knotweed, you won’t want to miss these meetups!

Uncontrolled knotweed can easily reach over 12 feet in height.

The details

Matt Distler, Conservation Program Manager at Oxbow Farm & Conservation Center, will discuss the history and ecology of knotweed and give a tour of experimental control areas where different herbicide formulations have been assessed (in collaboration with King County Noxious Weed Control Program) and where different manual removal methods are being tested for use on small patches. Options and challenges for removal on organic-certified farms (or other areas where herbicides are not desired) will be discussed.

We hope to provide useful background information on this weed and its control, but also to provide a forum for discussion of challenges others have experienced in removing this plant from working (agricultural, suburban, urban) landscapes.


  • Wednesday, Aug 21st | 7PM-8:30PM, with King County Noxious Weed Program Staff
  • Tuesday, Aug 27th | 10AM-noon

Light refreshments will be provided.


Oxbow Farm & Conservation Center, 10819 Carnation-Duvall Rd. NE, Carnation, WA 98014. Please use the Public Entrance off of 268th Ave NE (look for the “Public Entrance” sign with the orange border). Detailed directions can be found on Oxbow’s website.

This will be a walking tour/outdoor event, so dress for the weather, bring a water bottle, and wear sturdy shoes or boots.


Please email if you plan to attend. Note: If your group/farm/organization would like to set up a tour or talk to learn more about this weed and its control but is unable to attend on the dates listed above, please reach out to Matt!