The dual action formula of ACE Ready-to-Use Weed & Grass Killer Concentrate1 controls over 175 listed weeds and grasses. One ingredient works on contact, producing visible results within hours. Other ingredients move within the plant, penetrating deep to kill down to the root. With this fast-acting weed killer, weeds will be dead within 1 to 2 weeks. Apply this powerful weed and grass killer along fences; around buildings; on gravel and mulch beds; in cracks of walks, drives, and patios; and around perennial beds, trees, and shrubs. An application will be rainfast in 30 minutes. People and pets may enter the treated area after it dries. It's effective against some of the toughest weeds and grasses, including clover, crabgrass, dandelion, fescue, knotweed, and plantain. For best results, easily apply to weeds and unwanted grasses with a tank sprayer when the wind is calm, the temperature is above 60°F, and weeds are actively growing. When mixed as directed, 5 fl. oz. combined with 1 gallon of water will cover up to 350 sq. ft.