I have a Japanese Knotweed problem in a limited area (about 15x15 feet).
It is very difficult to dig up the roots because they can be a good 2 feet underground.
Therefore I am considering death by injection: cutting off the stalks about 6 inches above the ground and pouring imazapyr into the well of the stalk. Will this be effective? Is there a better approach?
One pamphlet I read described an experiment where they did something similar but used a mixture of glyphosate, triclopyr, and imazapyr. I am not really expert in different herbicides, so I am looking for some expert advice here.