Emerald Ash Borer FAQs

The Emerald Ash Borer is a beetle that feeds on ash trees. While not dangerous in its native habitat (Asia), this insect is devastating to all ash trees and will kill those that are untreated. EABs were found in Boulder in September 2013. Please contact us if you think you have Ash trees so we can measure your trees and provide options to help reduce the impact these insects will have on your property.

All species of Ash trees are affected, but not Mountain Ash, which is not a “true” Ash.

At this time, we are recommending an annual systemic insecticide application to all high-value ash trees to help protect the trees from initial attacks. Treatment options and results may vary based on tree size, proximity to known EAB activity, tree location, tree health, soil moisture, and insect populations/pressure.

Ash trees will need to be treated annually for their useful lifetime, so decisions will need to be made to treat or remove/replace trees. If you are going to treat your trees, please let us know as soon as possible so we can schedule your service, as timing is a key factor in successful control. Our arborists are available to discuss treatment options, timing, cost, and any other questions.

Your current “Ash Borer” spray is for Lilac-Ash Borers. EAB must be treated differently as some treatments for larger trees control both.

Healthy trees are known to respond more favorably to treatment programs. We highly recommend an annual nutrient program to care for your Ash trees for this reason. We also recommend supplemental watering during the winter months and during the heat of the summer.

Our nutrient program is NOT a fertilizer to make trees grow fast — it was developed to improve metabolic function, root health, and root vigor (healthy roots = healthy plants). If your Ash tree(s) is not getting a nutrient program, please call us so we can provide you with pricing information. 

Colorado’s dry, windy winter weather wicks moisture from trees. Our supplemental hydration program incorporates wetting agents/natural extracts that improve water absorption and retention and enhance the soil.

Pricing is determined by tree diameter and treatment options. We are happy to provide you with a free, no-obligation estimate and discuss treatment options.