Question
We recently planted a birch tree and about 3 days later, our daughter, sweet child that she is, decided to peel away about 6 inches of the bark all the way around the tree.  I know birches are suseptible to diseases and probably even weaker without its bark.  What can I do to help the tree heal or prevent it from getting any disease.

The tree was planted by a reputable nursery with appropriate fertilizer.

Answer
As long as the loose bark was peeled off and not the tight bark it will be OK. I doubt that the tight bark was peeled off. It would be difficult to get it off with out a knife. The tight bark protects the cambium layer of cells--this is the growing live cells that cover the woody cells. Garden type stores (nurseries) should carry a tree wrap-if you want you can wrap the tree where the damage occurred and this will protect it from drying out. Or doing nothing is ok. I would check once a week for any sawdust a sign that a borer insect has attacked. IF sawdust or holes are seen I would spray the area with an insecticide called Merit or Onyx. Do not use wound dressing on the area this will slow the healing process. I think the tree will be fine.