Newly planted trees should be staked only if they are at risk of being blown over or uprooted before they become established. Where prevailing winds are a potential problem, stake newly planted trees for about 3 months, and certainly no longer than a year. Drive 3 posts into the ground around the young tree. Make them equidistant from each other out about 4 feet from the trunk or just beyond the dripline. Loop soft cables of clothes line, or commercial staking material such as wire rope that is wrapped with protection such as a piece of old garden hose to secure the young tree. Allow some “give” in the lines, to avoid stressing the trunk excessively on a windy day. Check often to make sure the lines do not bind or injure the trunk in any way. Staking is controversial because a developing tree that has been braced for a long time often fails to develop a really strong root system, as it would have if it had to deal unaided with the natural swaying motion caused by wind. Other advantages of stakes are that they can prevent impact damage from lawn mowers and other yard care equipment, and they can also discourage deer from rubbing their antlers against the tree trunk.
For more information see file on Planting Trees.