Premixed for easy and effective weed control, this weed killer starts to work in hours. For use on unwanted vegetation, it is absorbed by the leaves, and moves throughout the entire plant, above and below ground. Roundup Xl tough and deep root weedkiller kills tough, deep rooted and woody weeds including brambles, thistles and nettles. It is inactivated immediately on contact with soil and is then broken down by soil micro-organisms, to allow replanting. Do not use on lawns or other wanted plants.