Ortho WeedClear Lawn Weed Killer Concentrate kills all types of weeds (as listed) without harming your lawn (when used as directed). The formula is rainproof in 1 hour and is fast-acting - you'll see results in just one application. It kills over 200 weeds down to the roots, including dandelion, chickweed, clover, crabgrass, and foxtail. Ortho WeedClear Lawn Weed Killer Concentrate is for use on grasses, including Bermudagrass, Buffalograss, Fescues, Kentucky Bluegrass, Ryegrass, and Zoysiagrass. Apply when weeds are small and actively growing in the spring or fall. For crabgrass, apply in the spring before it is 4 inches tall or when it is first noticeable in the lawn. This product is a concentrate. It cannot be applied directly out of its container. Use 2.5 fl. oz. per gallon of water for every 400 sq. ft. It can be easily applied with an Ortho Dial 'N Spray or tank sprayer. Use Ortho WeedClear Lawn Weed Killer Concentrate to kill weeds to the roots!