Please help! I found this growing around the playground at my daughter's nursery school, and need an ID ASAP. I can generally pick out poison ivy a mile away, and this does have some of the usual earmarks, but it doesn't look quite like any of the varieties I'm used to seeing around here (Long Island, NY). It was intertwined among other vines and shrubs. I noted one (just one) stem had four leaflets instead of three, although there was a heck of alot of it that had three.