river birch trees
3 River birch trees losing leaves from tops of branches. Trees are low on iron so I will inject them but they look like they have some kind of insect problem. Outer edges of trees are going bald. Leaves are yellow.
My best guess is that if they are losing leaves from the crown (top of the tree) it is the bronze birch borer. There is not much you can do. Can you send me a few pictures. please send it to firstname.lastname@example.org