Submitter has sample
EDRR Status: Local expert notified
massive leaves, massive stalks: 4-8 foot tall. plants mostly in large cluster, and spreading across about .25 acres.
Thank you for reporting this infestation of knotweed. Japanese knotweed is a significant problem invader in riparian communities within Clackamas County. The Clackamas Soil and Water Conservation District is working with regional partners to map and catalog known infestations of knotweed to help prioritize future control efforts.
Work on knotweed in the Sandy River Basin has been underway for several years and we are working with regional partners to continue this effort. Please contact me if you own or manage this parcel so we can arrange treatment. Otherwise we will try and work with the effected landowner to control the knotweed on their property. For more information on knotweed please review these online resources for more information on knotweed.
http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/21809/em9031.pdf
http://your.kingcounty.gov/dnrp/library/water-and-land/weeds/BMPs/Knotweed-Control.pdf
http://www.imapinvasives.org/GIST/ESA/esapages/documnts/polycus.pdf
Again thank you for reporting this invader. All the best,
Sam
______________________________________
Samuel Leininger
WeedWise Program Manager
Clackamas Soil & Water Conservation District
221 Molalla Ave. Suite 102
Oregon City, OR 97045
503-210-6006
weeds@conservationdistrict.org
www.conservationdistrict.org
______________________________________
Samuel Leininger
June 19, 2013, 1:33 a.m.