Trees missing bark
This animal damage is often seen in winter when food is scarce. The near ground damage could be rabbit, porcupine or opossum or other animals. Higher up it is likely porcupine, squirrel or even deer. Woodpeckers can cause large areas of bark to be damaged, while they look for insects. Squirrels will strip bark, too.
The first picture looks like bird or squirrel damage. The second, rabbits or porcupine, and the third looks like squirrel or porcupine.
There are a number of ways to protect individual high value trees with temporary barricades, flashing temporarily placed around individual tree trunks, etc. Any tree trunk barricades need to be removed before the tree grows into them.
Here are some articles showing these devices.
Once damage is done there is nothing you can do for the tree other than protect it from further damage , and give it good care through the growing season- prune off damaged or broken branches, and provide supplemental water during droughts. If the bark isn’t removed all the way around the branch or trunk(known as ‘girdling’) the branch or tree is likely to survive. Deer Fencing for the whole area can prevent deer damage, but small animals will still be an issue. It isn’t practical to protect more than a few select trees, perhaps the ones near the edge where they enhance your view from your home. Thanks for using our service.