Question
There is a series of holes, about one-quarter inch in diameter, that form a ring around the trunk.  The "ring" is about 15 feet from the base.  There is also a reddish sap that comes from the area of the holes.  Seattle WA area.

Answer
This is woodpecker hole from a bird called a sap sucker. The bird makes a line of holes and insects are attracted to the sap that forms in the holes. The bird returns to eat the insects. this will no harm the tree. If you want to keep the woodpecker from coming you can spray the hole area with any common insecticide and kill the insects and the bird will have nothing to eat and go away.