Tree guards can be purchased in a variety of materials (from plastic to metal) and should be placed around the trunk of young trees until they outgrow them, usually when the tree is between 3 and 5 years old. Make sure that the guard you choose is not installed too loosely or too tightly around the trunk of the tree, which could deprive it of moisture and room to grow. For added protection, you can create a small enclosure using fence posts with deer fencing, chicken wire, or bird netting around the tree in a diameter wide enough so that deer can’t easily reach the leaves and branches. If you are growing soft fruit (such as blueberries), you might drape the bush in bird netting when it’s producing. Some tree protection supplies can be found at local garden supply stores. In addition, some online suppliers may specialize in this type of product. Examples are below.
Orchard Innovations - offers products designed to protect fruit trees from animals, insects, and weeds, as well as other supplies for training and supporting trees and berry vines.
Many local hardware stores carry tree protection supplies.