How to control Japanese knotweed
I have discovered that the nice screen growing along my property line is Japanese knotweed. Any tips on how to remove or control it?
?Jack Wheeler, Charlottetown
Oh dear, this escaped ornamental is even worse than goutweed (Aegopodium podagraria). Classed as a noxious weed in many provinces, Japanese knotweed (Polygonum cuspidatum) has shoots that can penetrate asphalt. Chop it back to the ground, then cover the area with a layer of heavy black plastic held down with bricks. Leave for several weeks in the sun to fry the remnants beneath. Then cover the whole lot with dampened newspaper and another layer of black plastic. This is a tough plant and it will take a while to get rid of it cheaply. The alternative is to dig it out with a backhoe. I?d go with the plastic.
?Marjorie Harris, Editor at Large