Devil's walkingstick, Hercules club (Aralia spinosa)
This tree's leaves are huge and doubly compound. Twigs are armed with stout spines, and leaf stalks are sometimes armed with prickles. Attractive, juicy, dark purple-black berries are borne in the fall. root sprouts often make extensive colonies.
To learn more about Devil's walkingstick, visit its profile at the USDA Plants Database