Dear Michael,

Thank you for contacting Ask Extension.  Are you asking about removal because your Ash Trees are doing poorly?  Did your Arborist indicate the problem is due to an insect infestation? Although there are several insects that can affect Ash trees, the one kills Ash trees in a few years is the Emerald Ash Borer.  This insect is very difficult to detect and is regrettably in the Front Range region. I am making the assumption that this is the insect infecting your trees.

Larvae feed under the bark, eventually girdling the tree and cutting off nutrients. Ash trees are typically killed within 2-4 years of first symptoms, even previously healthy tress.  This article includes a web site that will provide possible Emerald Ash Borer treatments and recommendations for you to make an informed decision. 

https://planttalk.colostate.edu/topics/trees-shrubs-vines/1735-ash-trees/

I hope you find this information helpful.

Regards,

Marion C.

El Paso Master Gardener

Thank you for the information Marion. Currently our trees are healthy so I would rather keep them and probably treat them. I dislike taking down the trees because they provide so much shade.  Taking them down would take a long time for subsequent plantings to grow. Longer than my wife and I have anyway.