A tree forms callous tissue to cover wounds. How quickly a tree heals depends on the size of the wound and where it’s cut.
The Sugar Maple cross-section at the top of this post shows a well healed wound. You can see the cut and the callous tissue that closed the wound.
Below is the same wound from the outside.
This Choke Cherry stump grew around suckers cut years before. I can’t say the tree was ‘healing’ but the picture demonstrates how a tree envelops objects.
In elementary school we’re taught to count a trees rings to learn the trees age. Growth rings also give us a clue to a trees health.
The growth rings on this White Oak are very close for many years. There may have been a drought, lighting strike or a pest attacking the tree.
The rings are so close because the tree was healing from pruning and lost a lot of its canopy causing stunted growth.
The Three Cut Method of Pruning
When splitting wood I see all kinds of neat things demonstrating how trees grow. The video below showcases healed wounds and shows the three cut method for pruning trees.
If you just want to learn about the three cut method skip to the second half of the video.