How do I protect my ash tree from emerald ash borer? Are there any companies in the capitol region that provide this service?
If it is a smaller tree, you might be able to use a systemic insecticide to protect it.
https://www.bonide.com/products/insect-control/view/609/annual-tree-and-shrub-conc
You’d need to treat every spring. For a larger tree, you could contact a reputable tree service for injection treatments.