BioAdvanced Extreme Crabgrass Killer is a specialized crabgrass solution that kills down to the root. The exclusive formula kills even large, hairy and smooth crabgrass. In addition to fighting off crabgrass, it kills grassy weeds including foxtail, sandbur, bermudagrass, and more. For best results, apply at the first sign of weeds and when temperatures are below 90 degrees. It can be used on Northern turfs such as Fescue, Perennial Ryegrass, and Kentucky Bluegrass. It is NOT intended for use on St. Augustine, Floratum, Bermudagrass, Bentgrass, Zoysiagrass, Centipede or Bahia lawns. The product is rainproof in just one hour after application, meaning no rain or water will impact the effectiveness of the formula. BioAdvanced Extreme Crabgrass Killer measures 32-ounces and treats up to 5,000 square feet.