Hi Laura:

In general, no matter the cause, trunk damage exposes the secondary layer of tissue that runs the nutrients and water up and down the tree. If there is too much damage, the tree will die.  Healthy trees usually recover from wounding quickly. Try to keep your tree growing vigorously by watering it during the summer and dry winter when the ground is not frozen, and providing proper fertilization. This will increase the rate of wound closure, enhance callus growth and improve the resistance to decay mechanisms.

That being said, I think this could be a cause of sunscald.  If the side of the trunk that is damaged is on the south or southwest facing side, it is a good candidate.  Below is a bulletin that will go into more detail on the condition, prevention and treatment.

Environmental Injury: Sunscald and Sunburn

Another possibility could be the banding wrapped on the trees was loose and moving/rubbing on the trees with movement by the wind.  As you have removed the material that will no longer be an issue.  

Just in case it is deer rubbing, I'm attaching a bulletin that will go into further detail and give you options for protecting your tree from further animal damage.  

How to Protect Trees and Shrubs from Animal Damage Over Winter

Thank you for your question,