Image Herbicide Lawn Weed and Crabgrass Killer Concentrate kills major broadleaf and troublesome grass weeds including dandelions, chickweed and clover as well as crabgrass and foxtail. This systemic weed killer is a concentrate that should diluted with water (always follow directions on label for application instructions). Apply to your lawn when daytime temperatures are between 50°F and 90°F. This bottle will cover up to 4,000 sq. ft.