There are many ways to associate your label with your tree. A simple zip tie or wire around a sturdy branch is one way. This seems to be the norm from what I have seen in some orchards and on the internet. It will require a little vigilance on your part to make sure the label does not grow into the tree or chafe the bark. Baby trees may not be able to support the weight of a tag until they are older. Also keep in mind that the branch you hang it from may not live as long as the tree itself.

My preferred method is to fix the label to a stake in front of the tree. For me labeling a tree should be a one-time event that requires zero maintenance in my lifetime and beyond. Ideally the stake should be made of something that won't rust, rot, or degrade. I make stakes out of old copper plumbing pipe and use a stainless steel eyebolt to hang the label. You have taken the time to invest in a label that will last a millennia, why not ensure it gets seen 100 years from now? Ultimately you will have to decide what best fits your individual situation. Good luck and happy backyard orcharding!