Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on Oct 26, 2025

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

Description of specimen

Estimated 20 x 40 foot infestation of Japanese knotweed.

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

The Japanese knotweed is just north of Mapleton Drive on the edge of a small canyon in West Linn. 45.38528N, 122.62924W

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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