Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on Aug 20, 2015

Submitter does not have a specimen
EDRR Status: Local expert notified

Description of specimen

See above

Commentary

Good Afternoon Ms. Lamoreaux,

I want to thank you for reporting this infestation of knotweed. This species is a significant problem invader within Clackamas County. The Clackamas Soil and Water Conservation District is working with regional partners to map and catalog known infestations to help prioritize future control efforts.

We are currently treating a number of patches at priority sites within that area and across Clackamas County.
Your report will help us to prioritize future knotweed treatments. So thank you for taking the time to report this invasive species. Please feel free to contact me if you have any additional questions.

Again thank you for reporting these invaders. All the best,

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
Sept. 3, 2015, 2:25 a.m.

Remedy

Oregon State University's Solve Pest Problems page has some great information about how to get rid of knotweeds Solve Pest Problems

This is a tricky weed to manage. Consider reaching out to your local Soil & Water Conservation District for technical advice.

Location

Located on public land on Still Creek to the SE side of the bridge that is closed there is Japanese Knotweed growing. It is near the banks of Still Creek and is just off the foot path that runs between cabins on the forest service land.

Expert Reviewer

Samuel Leininger
Clackamas Soil and Water Conservation District
4-County Cooperative Weed Management Area
Columbia Gorge Cooperative Weed Management Area

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