Answer: I wish there were an easy answer. Knotweed has been successfully controlled by hoeing, digging, grazing goats and timely applications of herbicides. But, there's no specific control measure; you may have to resort to all of the above. Just so you know what you're up against, here's a publication from University of California that will explain the growth habits and control of this terrible weed:
Best wishes with your project!
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