Spectracide Weed Stop For Lawns Concentrate, Ready-to-Spray, 32-Ounce KILLS WEEDS, NOT THE LAWN: Wont harm lawns when used as directed  kills more than 200 types of weeds as listed. CONTROLS ALL MAJOR BROADLEAF WEEDS: Controls dandelion, chickweed and clover (see product label for complete list). KILLS THE ROOT: See overnight results. RAINPROOF: Rainfall or watering 6 hours after application will not wash away effectiveness. COVERAGE: 32 ounce bottle treats up to 16,000 square feet and 40 ounce bottle treats up to 20,000 square feet.