And on the flip side -- we've been purposely de-fencing our property for the past several years. We no longer keep any livestock and I absolutely love the open space look rather than boards or wire. Have you tried dog treats to make friends with your confused canine neighbor? Or perhaps meet with the neighbor AND the dog so the dog recognizes that you are not a threat. Unfortunately dogs don't understand property lines. As you said, he is likely just defending 'his' turf. Good luck.
