Q.: I have six 90-foot tall oaks in my yard. As the leaves fell, I see that many are covered with tiny button-shaped things. It seems worse with the white oak rather than the red oak. Earlier in the ...

Galls are growths on leaves, stems, branches, trunks, and roots caused by various agents. But they are usually induced by either insects or a fungus of some sort. The exact manner in which insect ...