My aspens have a sticky, clear residue on the leaves, what’s wrong?
The sticky honeydew residue is caused by aphids. You can check for the little insects on the under side of the leaves. One easy way to treat this problem is to spray the tree down with water. Aspens are often sensitive to chemicals (turn black) and water is a safe treatment. Products such as cygon, orthene, or isotox can also be used.
