Land Plants - invasive

Knotweed (species unknown) (Fallopia spp.) on May 26, 2025

Submitter has sample

Description of specimen

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

Knotweed along willamette river greenway. Big enough that it’s spreading, swollen enough that it seems containable with action.

Expert Reviewer

Jacob Rose
Institute for Natural Resources

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