This product kills crabgrass and other listed grass weeds – to the root. And it will not harm your lawn when used as directed. The formula is ideal if you have crabgrass invading your lawn or if you missed your pre-emergent crabgrass control application. The convenient sprayer connects to a garden hose and automatically dispenses the crabgrass killer. One bottle treats 5,000 square feet. Controlling crabgrass and other listed weeds in your lawn has never been easier! Specialized Crabgrass solution. Kills Crabgrass to the root. Even kills large Crabgrass. For use on cool-season turfs (Fescue, Perennial Ryegrass and Kentucky Bluegrass - temporary discoloration may occur on Kentucky Bluegrass lawns, but they will recover). Rainproof in 1 hour. Convenient Ready-To-Spray application.