Ortho WeedClear Lawn Weed Killer Ready-to-Spray’s fast-acting, ready-to-use formula is rainproof in just one hour. Plus, you can see results in just one application. It kills over 200 weeds down to the roots, including dandelion, chickweed, clover, crabgrass, and foxtail. And won’t harm your lawn, when used as directed.  Jeff