Land Plants - invasive

Japanese Knotweed (Fallopia japonica) on Jul 5, 2013

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

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

Description of specimen

several small to medium clumps of knotweed.

Commentary

sorry for all the pictures. I hope it's not too many.

Reporter
July 5, 2013, 12:39 p.m.

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

On an island in the Willamette River between Green Island and Lanes Turn Road. The red dot is placed very precisely in a small opening that is ringed with medium and small clumps of knotweed. Other small populations extend south toward the mainstem Willamette. The attached pictures have geotags that appear to be accurate.

Expert Reviewer

Mr. Vern Holm
Director, Oregon Vegetation Management Association

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