Ask Mr. Smarty Plants

We do think you have bees. They are probably feeding off of honeydew which, to put it as delicately as possible, is a waste product of either scale or aphids. This was a particularly bad problem about this time last year in Central Texas, and seems to be cropping up again. The honeydew is sweet and sticky and often rains out of infested trees to mess up cars, sidewalks and your odd dog, if he doesn't keep moving. The bees are apparently attracted to that substance and may very well be nested somewhere in the thick foliage. Here is a YouTube video on bees nesting in a live oak tree.

Here is a previous Mr.Smarty Plants question on aphids in live oaks, with several additional links, all in Central Texas. Now, here is the thing - if you have bees feeding on aphid honeydew in your tree, the smart move is to leave the whole thing alone. The aphids will die, leaving eggs that can't be disturbed by pesticides. The bees will either leave or hibernate in that tree. Insecticides would be most likely to kill the predators, like ladybugs, that go after the aphids. They could also kill the bees, which are beneficials, in terms of the pollination work that they do. Either spraying that tree with water, as suggested for the aphids, or spraying with pesticide, ditto, is not going to make the bees happy. While the bees are relatively harmless beneficials, mad bees can do considerable harm. Getting up in a tree to investigate may very well require sudden movement, called, "falling," out of the tree, and the climber may be accompanied down by even more angry bees.

Our suggestion is that you wait for cold weather to clear out the infestation, and then, early in the Spring, when the aphid eggs that have overwintered start to hatch, that is the time to start with the water sprays to try to get rid of them. Read this University of California Integrated Pest Management article on Aphids for more information on their life cycle, etc.