Cats are attracted to the scent of trees and are known to climb and scratch at them. One way to keep cats away from the Christmas tree is to use cat deterrent spray, which can be found at most pet stores. This spray is designed to keep cats away from areas that they shouldn't be in, including Christmas trees. Another option is to place a physical barrier around the tree, such as aluminum foil, to make it uncomfortable for cats to approach. Additionally, you can try giving your cat a new toy or scratching post to keep them occupied and away from the tree.