You're having similar troubles with your neighbor as we're having with the one on our west side. Life was fine for about 17 or 18 years here when he and his wife lived in Taxachusetts and rented out 1 to 3 years at a time to various people. Never any problems with them, and I go naked all the time outside (like the neighbor on the other side).
They moved back 2 or 3 years ago and promptly put in some more trees about 6 or 8 feet from our property line. This is after getting it resurveyed and putting ugly metal stakes about every 75 ft. He was using a tree planting service using a back hoe. This was in 2018 with gobs of rain. Soil was soft. No need for a back hoe. They cut our phone line in 2 places. Then he claimed that HE has no easement for OUR phone line on HIS land (there is, almost nation wide: 10 ft each side of the line). We had internet and phone with Centurylink at that time. They came out to put in a new line. He stood out there defying them not to put it on HIS land. They came back later and between us and CL came up with a way to put a new phone line completely on our property.
The back woods had gotten grown up. So, he hired an outfit with a big CAT with a big flail mower on front to whack down everything between the trees. Some chunks were hurled over this way.
He uses a 30-06 or something similar to shoot hooved rats in his cleared back property now. No problem with me on this as long as no chance in the bullets crossing over our land. Have alerted neighbors who sometimes sneak across the very back of his property about this. We used to hike back up the big dam and across the lower part of his property. His wife almost attacked us one day when she saw us doing this. Guess she knew about his shooting tendencies. Didn't know about it then. Have had to relocate a people crossing bridge from his property on the trails I maintain down there to a spot on our property.
He's a good guy, Vietnam vet and all same year over there as me, but he's a dork.
Ralph