Hello Maureen,

Thank you for reaching out to Ask Extension.  The tree(s) in your picture are indeed Ash trees. 

As you may know, the Emerald Ash Borer (EAB) has been identified and confirmed in a small area of Arapahoe County, within the City of Littleton near the border with Englewood, Greenwood Village, and Centennial.

Since you have Ash trees, now is the time to make a plan for them. If they are large and healthy trees that you wish to protect, you will need to have them treated for them treated at some point.

A few things to consider when deciding WHEN to start treatment:

· The question of when to treat comes down to where you live in proximity to where EAB has been confirmed, peace-of-mind, and the financial investment. 

· EAB is hard to detect for the first few years inside a tree. EAB has already been confirmed in several areas throughout the Front Range. And while EAB has been discovered in urban Arapahoe County, it is unknown how much of an impact it will have in the next few years.

· If the ash tree is healthy, you can start treating the tree AFTER it has been infested with EAB, if you catch EAB early. Research has shown if the tree hasn’t lost more than 30% of the crown, insecticides are likely to save the tree. 

· Saving the ash tree will likely mean the financial investment of treating the tree for the rest of its life, or as long as you own the property. 

· Regardless of when you start treatment, the top priority should be keeping your trees as healthy as possible!

Here is a link regarding the signs/symptoms of EAB: https://csfs.colostate.edu/wp-content/uploads/2016/04/FINAL_EAB_QuickGuide_Revision_25APRIL2016.pdf

Arapahoe County in partnership with CSU Extension has a go-to “hub” for information: http://www.arapahoegov.com/emeraldashborer

Here is a link to the Emerald Ash Borer Treatment and Planning Q&A: https://arapahoecounty365-my.sharepoint.com/:w:/g/personal/lmayer_arapahoegov_com/EfCHUg46ugZAgVgP3hO7rqoBIvT0eBTMYxtcap4GSyvLCg?e=EeX0h1

When hiring a tree care professional, ask for credentials. Arborists should be certified through the International Society of Arboriculture: https://www.treesaregood.org/

Some municipalities like the City of Littleton have a list of certified tree care companies approved to work within the city

I hope this helps!

Dawn