While Christmas trees are generally considered safe for dogs, there are a few things to keep in mind. The sap from the tree can irritate your dog's skin and mouth if they chew on the branches or ingest it. Additionally, the needles can cause gastrointestinal upset if swallowed. Make sure to keep an eye on your dog around the tree and be sure to keep any breakable ornaments out of reach. If you notice your dog is chewing on the tree, try redirecting their attention with a toy or treat instead.