Question
My oak trees have horned oak galls.Is there any chemical that will treat this condition? Thanks

Answer
Curt:

Chemical control isn't usually called for this pest. Like many other tree insects, there are usually predators that keep the pests in check.

If the population is at a level where chemical control is definite option, see a product called Insect Control for Trees and Shrubs by Bayer Chemical Co.  It contains Imidacloprid.  The Bayer product is mixed with water and applied to the soil.  The tree roots pick up the chemical.  This chemical can control many other insects as well.  Be sure to read and follow the directions according to the label on the bottle.

Steve