I have 3 quaking aspens that we planted about 10 years ago. Largest of the 3...

Asked June 27, 2014, 7:31 PM EDT

I have 3 quaking aspens that we planted about 10 years ago. Largest of the 3 has a lot of dead branches. Each year there are a few small dead branches or sub-branches that need to be pruned, but this year it is half the tree. I took some photos of bark/trunk with possible cankers or bores? Thanks for any advice you can give. Steve

Dakota County Minnesota

3 Responses

Quaking Aspen (Populus tremuloides Michx.) is one of the most widely distributed trees in North America. It is one of the first trees to populate an area that has been clear cut by timbering operations, by forest fires or other natural disasters. Although it readily spreads by suckering, It is a rather short lived tree, rarely exceeding 80 years, and is vulnerable to many diseases and other insults - as befits a first-growth tree.

In spite of all of that it is a lovely tree and we often want to see it live at least as long as we do!

The symptoms you are describing seem to fit within a list of common ailments - some of them fatal - that afflict our "popples". Canker diseases are by far the most serious causes of tree mortality. Here are some links that will tell you more about this problem:
http://www.na.fs.fed.us/spfo/pubs/fidls/decay/decay.htm
http://www.extension.umn.edu/garden/yard-garden/trees-shrubs/hypoxylon-canker-on-aspens-and-willows/
http://www.mntca.org/populus-tremuloides-quaking-aspen/

I hope that you will find a way to save these iconic trees. Please get back to us at AaE if you have further questions.


Thanks so much. I will look at those links. Your comment about suckering raised another question. The aspen suckers sprout in our landscape beds. I cut or pull them out, and if the node is particularly big and strong, I cut it out at the root. Does this practice stress or harm my trees? Thanks again.

Cutting out the suckers will not harm the tree but don't use an herbicide on any of these new trees because the poison will translocate back to the older trees and may kill them as well. Even if they don't die they will be injured enough to make them susceptible to insect and disease problems.