Set up physical barriers.
This is probably the best, and most permanent option, although perhaps the costliest as well. Many landowners have chosen to set up fences, netting, or some other physical impediments to the deer to protect their trees and gardens. If done right, this can be 100% effective.
Damage caused by bucks rubbing their antlers on small trees can sometimes be prevented by driving three sturdy wooden stakes or fence posts around each tree in late summer. Space the stakes or posts about 18 inches apart. Or you can purchase tree guards for each individual tree. Plastic or mesh tree guards are a quick fix. They wrap right around your tree’s trunk and prevent deer from rubbing up against the bark.
When deer rub their antlers on trees, they strip away the tree’s cambium. That’s the layer between the inner bark and the outer wood that helps nutrients move throughout the tree. Unfortunately, when the cambium layer is stripped off all sides of the tree, the damage is done. Now, there’s a good chance the tree won’t survive many more winters. But if the damage is only partial, your tree may be able to seal over the damaged area. Over time (several years or more), new bark will grow in and slowly cover the wounded wood. How well your tree will be able to repair itself depends on how many sides of the trunk the deer damaged and the depth of the wounds. Even if the tree does not die, the damage may be so extensive that it may never fully recover or even break off.
If the damage is minimal, you can aid your tree’s recovery by doing what is called bark tracing. You essentially cut out the damaged bark, which leaves a smooth wound that trees can repair a bit easier. With a super sharp and disinfected knife, cut about an inch wider than where you see damage, and you should be good!

No matter how much of the tree bark has been damaged, you will need to repair the wound. If the tree is simply scratched, wash the wound out with plain soap and water to help reduce the amount of pathogens that may be in the scratch and that could cause further damage. Wash the wound thoroughly with plain water after this. Allow the scratch to heal in the open air. Do not use a sealant.
Jagged wounds will interfere with the tree’s ability to transport nutrients so you will need to clean cut the wound. You do this by removing tree bark by cutting an oval around the circumference of the damage. The top and bottom of the wound there will be for the points of the oval. Do this as shallowly and as close to the wound as possible. Let the wound air heal. Do not use sealant. Instead, the tree will seal wounds with a "callus" tissue. The tree produces new wood to grow around the wound. This isolates and protects the wound from further exposure and damage.
Conclusion. Healthy trees usually recover from wounding quickly. Try to keep wounded trees growing vigorously by watering them during droughts and providing proper fertilization. This will increase the rate of wound closure, enhance callus growth and improve the resistance to decay mechanisms.
Hope this helps!

Thank you so much for the info!

Thank you for contacting ask an expert.