I have 4 little fruit trees and a couple little "guilds" a la Edible Forest Gardens set up. Last year the trees (apple and pear) were assaulted but the numerous elk and deer in our area. They survived, somehow, and the new buds are just starting to re-appear.
I want to put up a simple fence around the area. It seemed very modest and small when I paced it out and put T posts on the corners. I've seen others in this area using T posts to support a large "hoop" of fencing around little trees like this.