South Fork Skykomish Knotweed control approved
Greetings!
We are beginning to schedule our seasonal work to control invasive knotweed infestations along the Skykomish and Tye Rivers. Your property is located in the area where we are able to control knotweed this year. We are writing to ask your permission to check for and control knotweed on your property. There is no cost to you for this work because it is part of a larger effort to combat this invasive noxious weed along the Skykomish River and its tributaries.
The purpose of this effort is to improve and restore the riverbanks to increase bank stability, benefit runs of threatened salmon, and to preserve the natural and scenic beauty of the river. Knotweed is an invasive plant that can cause problems if not controlled. On rivers it crowds out trees and other plants that are better for water quality and bank protection. It is also difficult to control because it spreads by fragments in the water, so all knotweed plants along a river need to be treated to be effective. This is why we are asking your permission to include your property in our project area.
If you agree, our staff will visit your property to check for and control knotweed between late July to late September. We would notify you ahead of time when we know the specific date the work would occur on your property. For our project to be successful, we ask all property owners in the project area to give us permission to search for and control knotweed on their properties.
In 2025, the project surveyed 270 acres in the river corridor, walked/bushwhacked through 20 miles of riverbank, and controlled 2.
1 acres of knotweed. Although much work remains to be done, many previously infested riverbanks are now nearly knotweed free and are being replanted with native trees and shrubs by our project partners Sound Salmon Solutions.
We are getting closer to our goals of restoring the riverbanks to increase bank stability, benefit runs of threatened salmon downstream and preserving the natural and scenic beauty of the river.
All herbicide control for this project will be conducted with a state-approved, aquatic formulated, low risk herbicide and under a water-quality permit issued by the Washington State Department of Ecology. Please do not cut or mow the knotweed on your property before we treat it, because this will reduce the effectiveness of our control methods.
We are not able to control knotweed that is far away from the river or outside our project area. If you would like to learn more about knotweed and how to control it on your own, we invite you to visit our website at kingcounty.
gov/weeds or call us at 206-477-9333. We also offer workshops and instructional videos on knotweed control.
To help us schedule our field work, please complete and return the attached permission waiver by July 17th. This waiver allows the King County Noxious Weed Control Program and the crews working with us to survey and control knotweed on your property this year. Again, there is no cost to you for us to look for and control this noxious weed on your property, but we do need your permission before we can offer this assistance. You can also give me a call if you have any questions.
Please contact me if you have any questions or concerns and thank you in advance for your support of this effort to fight noxious weeds on the Skykomish River and its tributaries.
Sincerely,
Sara Stone (Price)
Skykomish River Riparian Project Manager
206-427-3679; sara.
price@kingcounty.
gov