Are there other more efficient ways of killing this plant, other than cutting it to the ground multiple times until the roots finally die out? I have made multiple cuts of this plant on the property that I regularly visit, and the plants ARE noticeably weaker, but I am not able to get down there often enough to kill the plant off. (I live in Portland.)

Reporter
Aug. 24, 2008, 8 p.m.

Dear Kari,

Thanks for reporting knotweed. It sounds like you have encountered a very serious infestation. It is possible that there are knotweed control projects happening on the Umpqua. However, this population may not be prioritized. The most effective strategy is to start upstream and work down since knotweed spreads primarily downstream.

I will notify the local watershed council and the cooperative weed management areas leads of this report so they can identify the land ownership, evaluate the urgency, and possibly control the population you reported. The links above have more information on how to control knotweed.

We hope you will keep on reporting! Check out this website for a list of plants and animals that are priority for early detection and control in Western Oregon: http://www.westerninvasivesnetwork.org/pages/plants.php

Thanks!

Tania Siemens
OSU Sea Grant/The Nature Conservancy
tania.siemens@oregonstate.edu

Tania Siemens
Aug. 29, 2008, 12:42 a.m.