Cottony Ash Psyllid
What is it?
Psyllids are tiny insects; the larvae are difficult to see with the naked eye. These insects attack Black and Manchurian Ash trees. Symptoms include wilting or curling leaves and sometimes premature leaf drop in the summer. Attacks may eventually kill the tree.
What can I do?
Spraying the tree with insecticidal soap may kill the pest. Timing is critical; it is best to spray as soon as leaves begin to emerge from the bud on your trees. As soon as the leaves begin to curl, it becomes extremely difficult to treat the pests.