Question
I have 10 year old oak tree that seems to be healthy, although some of the new growth seems to be void of leaves this summer.  I found shallow boar holes in the trunk and larger branches.  There are many boar holes and groups of them are strung in a line.  What causes this and how do I resolve?

Answer
The holes in a line are caused by a bird called a woodpecker. These birds make holes in the bark and insects come to feed on the sap produced and the bird returns to eat the insects. These cause no health problems for the tree. What is causing some limbs to not have leaves is not from the lines of holes. Sometimes the woodpeckers can ring a small limb killing it but this is not common. I can not tell from you description of the leaf problem what this might be.