Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on May 19, 2021

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

Description of specimen

Probably 20-40 stems all about 6-7 feet tall and mostly leafed out. I didn't see any flowers. I saw the patch as I was driving by, so I'm not sure if it extends further than what I saw on the corner.

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

Appears to be a patch of Japanese knotweed on the corner of 4th Avenue and a driveway heading up the hill to a few houses. Just ENE of Canemah Bluff Natural Area.

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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