Sudden browning of a tree's canopy is typically a major cause for concern. However, if it's late summer and you are seeing brown trees on the side of the highway, give these a second look. If they are black locust trees, this damage could be caused by locust leafminers and, while it looks bad, probably isn't a serious health concern for these trees. In this edition of "What's Bugging My Tree?" I'll talk a little bit about locust leafminer, what it looks and what it means for your trees.