I agree with Dee that spraying will work as well as anything, and better than most options. Around here multiflora Rose bushes have taken over in places. Its native to south China, and Korea. Was bought here for fence rows and such. Its an invasive species. It can get 10-15 feet high, and about the same in width. That is one bush. You can't walk through the stuff because the stalks have very sharp thorns on them. Something that works to kill it is spray it with Crossbow and diesel mixed together. Multiflora rose is the first plant to get green leaves on in the spring, which makes it easy to identify. As soon as you see the green leaves is the time to spray it.