Identity of this plant
Hi, We started noticing this plant becoming more pervasive over the past 3 years in the forest around our cabin in Pine Grove, Schuylkill County. It has thorns and a very thin stem. This year it is climbing around grape vines. This is the first year I'm seeing berries on the plants. What is this thorny plant?
It's possible that it is a mature flowering jimsonweed. I have attached a photo of one as well as a jimsonweed infestation similar to the one in your third photo. It's also possible it is a wild grape vine. The leaves of a wild grape vine are typically serrated but it's difficult to determine if the edges of the leaves in your photos are serrated. I hope this is of some help.