About a month ago I had a person prune a large white oak that is 150-180 years old. there were a few large branches but most were 1-2" in diameter. Instead of going to each branch and using a saw to get a clean cut he used a long pole and pushed on the braqnches until they broke off. After the leaves fell the fall I noticed many stubs from 6-9" long are left on the tree. I am concerned that these rough stubs may invite deseas and harm the tree over the years. I contacted him again and he said I should not worry about the stubs. I want him to return and saw the subs off so there will be a smooth cut. I would appreciate your advice on the matter.