Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on Aug 7, 2023

Submitter has sample
EDRR Status: Local expert notified

Description of specimen

One large plant in bloom and two smaller, not yet blooming.

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

Three Japanese Knotweed plants were found behind a shed on my property, by a company that is trimming my trees. The largest is growing through a rhododendron and two smaller are growing in the dirt close by.

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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