2/4/D will kill them and nothing I know of will eat them if treated or not. You would have to hand spray to avoid getting spray on everything ,deer forage included. I have sprayed them right in the middle of the plant with good results and no over spray . I usually use some round up added to the mix for extra punch . I hand spray some nettles and canadian thistles and the odd burr dock . Jim
How much area do you have to spray? are they individual plants? liquid propane applied directly to the plant will freeze kill them or a steam jenny will kill weeds the Canadian Pacific Railway does all their tracks with steam and don't use weedkiller products anymore.
