Land Plants - invasive

Knotweed (species unknown) (Fallopia spp.) on Apr 7, 2026

Originally reported as Giant Knotweed (Fallopia sachalinense)

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

Description of specimen

In the neighborhood of Whiteford Bluff, there is a large row of them at the top of a creek and over in a vacant lot and I am sure that there's more of it somewhere else in the park too. The problem is it's not. We're on the salmon River and they don't spray it. They just let it grow.

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

I live in a tiny home in Mount Hood Village resort and I worked for Peninsula College with plant identification and Cedar River restoration near Seattle and there is giant knotweed invasion in the park. The Rv park is right on the salmon river it's over 125 acres and they are not treating it and they put it in a burn pile that's near the river and I feel like it's just going to spread:-(

Expert Reviewer

Avatar of Reviewer

Brendan Fordyce
Clackamas Soil & Water Conservation District

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