Answer: Newly planted trees should have several inches of mulch over their root zone year round. Be careful not to let the mulch touch the trunk, however, as this can encourage both rodents and rot problems.
The trunk may be wrapped or painted with white latex paint on the southwest side to protect it from sunscald or freeze/thaw damage during the winter.
It should also be protected against rodents including voles and rabbits by being enclosed in a loose fitting wire mesh cylinder that is bent outward at the base about a foot to eighteen inches and extends upwards well above any anticipated snow line to prevent the animals from reaching around it to gnaw the bark. The wire should also be covered with gravel at the base of the tree to discourage digging activity. Remove or enlarge the wire covering as needed to avoid constricting the trunk.
Finally, you may also need to use some sort of deer deterrent -- a fence is most effective but there are also some repellents on the market that may be helpful when applied (and reapplied) according to the label instructions.
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