Yes, real Christmas trees are generally safe for dogs. However, there are a few things to keep in mind. First, it's important to keep the tree out of the dog's reach so that it doesn't chew on it or knock it over. Second, the needles from the tree can be sharp and can irritate the dog's skin if they get too close to the tree. Finally, some dogs may have allergies to the tree's sap or pollen, so it's a good idea to monitor their behavior and see if they have any signs of an allergic reaction.