Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on May 18, 2016

Originally reported as Knotweed (species unknown) (Fallopia spp.)

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

Description of specimen

This fairly conspicuous patch only became apparent in the last few weeks, and the cluster of knotweed stalks is well over 6 feet tall and at least 4 feet in diameter; there are several smaller clusters nearby.

Commentary

None

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

Along west bank of Boardman Creek slough that runs along the west edge of the Trolley Trail; approximately 100 feet south of Roethe Road.

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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