KleenUp® “HE” High Efficiency Weed & Grass Killer RTUKleenUp's High Efficiency is formulated to kill weeds, grasses, & brush in hours. Provides contact control and kills to the root so weeds don't grow back. One application kills weeds and grasses. With just one quart, you can treat up to 1,000 sq. ft. Kills weeds, grasses and brush, roots & all High efficiency formula, one gallon of finished spray treats 1,000 sq. ft. Economical to use Visible results in hours Use around trees, gardens, sidewalks,