It looks like greenbriar but has no thorns. Do not let it get started, because it’s hugely invasive. Of all the vines on this list, it may be the hardest to control.

PHOENIX (KPNX) - A kayaker in Arizona says he helped remove about 40 thorns from a wild donkey in pain, an encounter that will stick with him forever. Travis Ward has been kayaking for about a year ...