To protect our young fruit/nut trees, we use two layers of protection. On the outside, we use sheep wire or something like that to keep the deer from eating the tender shoots.  UFA has lots of choices for rolls of wire.

On the inside, we use hardware cloth.  We buy 1/4″ square. The hardware cloth helps protect the bark from voles and other little creatures.

So far this system, although time consuming to setup, has worked like a charm!  The only challenge is if you don’t mulch enough around the tree, it makes it difficult to remove large grasses or thistles.