And the Walls Came Tumbling Down

My dog is now leaving the planters alone, thanks to the plants filling in and the lawn being a nicer place to lay, but now I have a new problem.
Shortly after we got our dog, our neighbor supplemented his pack of small happy canines with a larger puppy. This dog has been significant trouble, jumping over the wall, escaping his yard, etc.
Through the strategic application of dog treats, I've convinced this new dog that he doesn't need to snap at me but that doesn't mean he's become friends with my dog. The two snap at each other over the wall constantly. The fights have become aggressive enough that they're knocking bricks out of the 60 year old wall that separates our yards.
Gotta do something about that while I still have a wall.