Preventative Treatments
There are currently 3 treatments that are recommended as being effective for the Emerald Ash borer as determined by a collaborative document from 5 Universities called Insecticide Options for Protecting Ash Trees from Emerald Ash Borer . A number of new products are currently being tested that may be added to the list in the near future. Be sure to keep up on the latest research and do your due diligence before determining what direction to go with treatments as the science is evolving and new information is emerging quickly. Also be aware that there are a number of products that are being marketed that have no proven efficacy. Store brand 2.94% imidacloprid formulations are only effective on small trees under 8" diameter (DBH). Professional strength tree formulations with the 2X Imidacloprid label must be used for trees larger than 8" diameter.
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