Question
I live in San Antonio Texas and have a very large hackberry tree in the back yard that covers approx 75% of the yard.  The plants, furniture and concrete are covered with a black film that is very hard to remove.  The leaves appear to have dried out and they also are spotted black.  It also appears that some type of insect is also on the leaves.  This is the first time that we have had issues like these other than sap being released in the past.  What should I do to take care of the problem or who can I call locally that can help with the problem.     Thank you,  Greg

Answer
This is an insect called an aphid. They suck the plant juices and secrete a substance called honeydew which is high in sugar content and sticky. A sooty mold will grow on the honeydew causing the black on everything. Control the aphids and the sooty mold and honeydew will go away. Next spring treat the tree with an insecticide called Bayer Advanced Tree and Shrub Insect control. This is applied to the soil around the tree and the roots will transport the insecticide to the foliage and twigs and when the insects suck the juices they are killed. It will last the season long. Check with your local nursery for this product. Here is a web link to the product.

http://www.bayeradvanced.com/product/Tree-Shrub-Insect-Control/concentrate.html