The emerald ash borer has been trapped in far eastern Pulaski County. Three individuals were trapped at the Bee Rock Campground near the Rockcastle River. Just because EAB was confirmed here, it's still hard to know how widespread the critter is.
Specialists at the University of Kentucky recommend treating high value ash trees. I would certainly concur. Unfortunately, the best time for treating trees is in the spring. So, for now, not much to do.
What you can do now is this: read up about the pest and its treatment options: http://www.emeraldashborer.info/files/Multistate_EAB_Insecticide_Fact_Sheet.pdf. Most of us will go with the homeowner option of imidacloprid (Bayer AdvancedTM Tree and Shrub Insect Control or OptrolTM). If your tree is less than 20 inches in diameter, it can be treated successfully. It takes 4 to 6 weeks for the pesticide to be taken up and distributed throughout the tree.
Imidacloprid should be applied in mid-March to late April. The rate is dependent on how large the tree is. If you need help measuring, please let me know as I have a diameter tape that measures trunk diameter. This treatment will have to be repeated on an annual basis.
For more information or questions, please don't hesitate to call the Pulaski County Extension Service at 606-679-6361 or email me at firstname.lastname@example.org