Knowledgebase
Dying Ash Tree #805292
Asked August 08, 2022, 5:07 PM EDT
My west-facing ash tree has been dying from ash borers (not emerald) for some years now. I have tried to nurse it alone for the excellent shade it provides. From the picture, you can see that the central branches are all bare. I haven't touched them but recently had several other dead branches removed, which prompted new growth. As you can see, several lateral branches are bowing down instead of up, and yet they are overgrown like crazy. I'm concerned that when winter comes, any snowfall will be enough weight to strip them all the way down and they'll take some trunk with them. I'm inclined to trim them back---there are about three---but that would mean taking off four to five feet from the ends of these branches. OK to do? What do you think?
Jefferson County Colorado
Expert Response
Hi usersuz,
While your tree may have taken a lot of damage from the borers you mentioned, it's pushing out a lot of growth so it appears to be very much alive and not dying! I would first recommend cleaning out the dead branches (I'm largely seeing those on top). You can double check that they're dead by scraping the bark of the branch with your fingernail - if the cambium underneath is still green, it's alive and may leaf out again. If it's brown, it's dead and can be pruned, using the three-cut method (explained here).
In terms of the lateral branches, I do think that it's a good idea to prune them in order to prevent snow loading and damage. However, pruning of these branches will be more complicated since they are living. The diameters of the branches will have to be evaluated, as well as the maximum amount of live wood that can be removed from the tree, which is not possible to do from a photo. I would recommend getting an arborist to evaluate and prune your tree for you (you can search for one here). Additionally, if you'd like to read more about pruning guidelines and methods, you can check out this resource: https://cmg.extension.colostate.edu/Gardennotes/615.pdf.
Feel free to reach out with any additional questions,
Thank you! ________________________________________ From: askextension=<personal data hidden> <askextension> on behalf of Ask Extension <askextension> Sent: Friday, August 12, 2022 1:31 PM To: usersuz Subject: Re: Dying Ash Tree (#0075223)</askextension></askextension>
You're welcome! :)
