Japanese Knotweed (Fallopia japonica) on May 21, 2013
Submitter has sample
Description of specimen
This is a patch of knotweed that has been reported to the City of Lake Oswego 3-4 years ago and they have not taken action. This is the only observed location on Oswego Lake where public access is available. The eradication now is so much more cost effective and apparently the City of Lake Oswego is either unaware of their responsibilities or is choosing poorly in their priorities.
Please educate or require the City to take action immediately. 503-635-0280
Commentary
Expert Reviewer
Samuel Leininger
Clackamas Soil and Water Conservation District
4-County Cooperative Weed Management Area
Columbia Gorge Cooperative Weed Management Area
Thank you for reporting this infestation of knotweed. Knotweed is a significant invader in riparian communities within Clackamas County. The Clackamas Soil and Water Conservation District is working with county and regional partners to map and catalog known infestations of knotweed to help prioritize future control efforts.
I have forwarded your report to land managers for the City of Lake Oswego. Knotweed is one of our most widespread invaders, and can be very difficult to control. Unfortunately, the resources available to control this invader are limited in relation to the overall need. As such resources may not be immediately available for control, but the city has been made aware of the problem and working to find a solution.
Knotweed is also targeted for control only in late summer and early fall. As such, even if control is planned for the site, they will not be targeted for at least several months.
For more information on knotweed and its control and management check these online resources.
http://www.skamaniacounty.org/Noxious_Weeds/TNCreport.htm
http://www.imapinvasives.org/GIST/ESA/esapages/documnts/polycus.pdf
Please feel free to contact me if you have any additional questions and thank you for reporting this invader.
Sincerely,
______________________________________
Samuel Leininger
WeedWise Program Manager
Clackamas Soil & Water Conservation District
221 Molalla Ave. Suite 102
Oregon City, OR 97045
503-210-6006
sleininger@conservationdistrict.org
www.conservationdistrict.org
______________________________________
Samuel Leininger
June 5, 2013, 3:05 a.m.