I have two Norweigian Firs that line my driveway. One has a
problem. About a foot and a half above the base there are
small holes that go in a row; not completely around the
tree. The holes are the same size and about the size of a
small acorn from a live oak tree (elongated, not fat).
About another six feet up, there is another group of the
same holes. These holes have sap coming out of them. Is
this some kind of insect or is it a man-made problem? If it
were man-made, would the holes harm the tree if there was
sap coming out? If it were an insect, what kind is it and
how should the tree be treated?