My wife did that once too. I found out when the NEW neighbor came over screaming about his tree the following weekend????
The story I found out later....Apparently she was mowing the back behind the garage with the Cub and the boys were in the side yard, boys being boys, something happened and one was screaming bloody murder, she looked over to them and promptly climbed a $135.00 blue spruce that the neighbor had put in a few weeks before. I had come home from work not knowing a thing. Hey, the tree was behind the garage, how was I supposed to know? I left in the dark and came home in the dark.
When I saw the tree I was very impressed, she cleaned that baby bald on one side. Cubs being what they are, didn't hurt it a bit, quick touch up on the blades, good to go. And thankfully nobody was hurt, just the tree.
Well anyway I paid for the tree and helped him plant another, and we actually became good friends over the years.