Question
I live in southern Arkansas and have three large hackberry trees in my backyard near an above ground pool. There is also a large oak tree in the group.  For the past three years the hackberrys secrete a sticky honeydew and the leaves become very pale yellow, turn black and drop.  All three of the hackberrys are affected badly.  The honeydew drifts onto the wooden deck surrounding the pool and also into the pool water.  What is this?  The trees are very tall and I can't get close to any of the branches to see them clearly.  Could it be whiteflies or aphids?  Is there a treatment for trees this large?  Could the water being drained from the pool with all the chemical it contains cause this?  Thanks for any help!

Answer
Sounds like aphids and they excrete the honeydew. Control the aphids and the honeydew will go away. Yes dumping the waste water from the pool with the chemicals will cause the tree problems generally by turning the leaves yellow. Make sure when you drain the waste water to move it out from under the trees. Water splashed out will not be enough to damage the trees. There are controls for aphides that can be applied under the tree and watered in and the tree will take the insecticide to the leaves and the aphids will be killed. Check with your local nursery fro one of these systemic insecticides.