We share a tree with our neighbor on both property lines. We agreed with our neighbor to trim the tree. Neighbor got a tree trimmer out. The tree trimmer was leaving after trimming it and I noticed the tree was cut unevenly and asked him if he was going to fix how uneven it was. The tree trimmer said he needed to talk to the property owner (our neighbor) and I informed him my husband and neighbor were the property owners and that he needed to wait for my husband to get home before he left. The tree trimmer then spoke with our neighbor and when my husband came home we found the tree trimmer cut our entire half of the tree limbs off but left our neighbors. My husband was upset. The tree trimmer told my husband I told him to cut it like that. Our neighbor is trying to say he also heard me tell the tree trimmer to do that and our side of the tree is “our responsibility”. We told him the tree was unsafe now and that we wanted it cut down. We even sent a letter from a certified arborist stating he recommended removal because the tree is basically doomed. Does our neighbor have anything against us? Our neighbor hasn’t responded to our letter. What are the next steps. Location: in CA.