To really get to the root of the problem and stop perennial weeds coming back you need to kills the unseen roots too and not just burn off the leaves glyphosate is the proven chemical of choice the world over for broad spectrum weed controlr once applied through the east to use spray gun with simple trigger applicatrion the glyphosate is slowly absorbed by the weed and moves systemically through the plant down to the roots as the weed feeds and growsr it works best when it is warm and