Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on Nov 20, 2021

Originally reported as Knotweed (species unknown) (Fallopia spp.)

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

Description of specimen

Empty lot full of italian arum and knotweed, and both populations seem to be healthy and spreading. Looks like a bad time. Its not my lot, I just happened to walk past it. :( Thank you!

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

Empty lot on the west side of 82nd Ave in Clackamas.

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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