This hedge is about 150 years old.. I have a photograph taken around 1890 and it is fully grown.
This shurb is native to this area (MA). It can be found growing wild in the woods and fencerows. It has blue berries in the fall. They are similar to wild blueberries. It also has thorns.
It has been neglected for several years and needs to be cut back. In 1954, it was cut back to five feet and sustained no permanent damage. It was largely defoliated down to stumps.
I need an identification and pruning advice.