Created with an exclusive formula, Roundup Poison Ivy Plus Tough Brush Killer Concentrate combines two brush-killing ingredients to penetrate the waxy leaves and brush of hard-to-kill weeds to kill them down to the root – guaranteed!* It also kills ivies and weeds like poison ivy, poison oak, and poison sumac, as well as invasive vines and shrubs like kudzu and wild blackberry. Simply mix 6 fl. oz. of the concentrate with 1 gallon of water in a Roundup Brand Premium Sprayer. Rainproof in 30 minutes, Roundup Poison Ivy Plus Tough Brush Killer Concentrate has visible results in 24 hours.