Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on May 20, 2023

Originally reported as Canada Thistle (Cirsium arvense)

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

Description of specimen

Its prickly and about two feet tall

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

(45.4430019, -122.6433930)

Behind a stone bench in the picnic 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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