Hi, i live in north jersey (essex county) and this plant was growing in my backyard.
The berries look very much like Blackberries, but they are redish-orange.
Where the berries have fallen from remains an orange cone shaped stem with 5 short leaves.
The branches were thorned and fuzzy green/burgundy.
The bush was big. Probably 10ft square.
Attached is an image i took on a camera phone.
Can someone identify???