I recently won a bid on rescaping 5 acres of semi-heavily wooded acres. I found out in less than an hour that my hired hands are seriously allergic to poison ivy, sumac and poison oak. I am not allergic so i will be able to get in there to spray it and kill the itchy vines so my guys can ditch the itch and get back in there. Problem is I'm less than sure what to put down to kill it and not harm the large crop of very nice growth trees that he wants to keep and also not inadvertently hit his patches of fescue he wants to keep. He's picky and im stumped. Can anybody unstump me? Thanka!