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mountain ash tree growth #929687

Asked April 26, 2026, 3:51 PM EDT

I have a mountain ash tree that is about 5 years old. It has hardly grown since planting it and for the last two years, it has not flowered or born fruit. I fertilize it every spring, using jobe's spikes. Can you give me a tip or two for jump starting this poor tree to grow, fill out and produce berries?

Itasca County Minnesota

Expert Response

Hi,

Can you please add a photo of the entire tree, and a close-up of the trunk where it meets the ground? Thanks.

MJ Replied April 26, 2026, 6:06 PM EDT
Thank you for your quick response. Here are photographs of the tree.

The first shows damage caused by a deer rubbing his antlers on the trunk. He did this the second season after we planted the tree and we did get blossoms and fruit the season after the deer did his damage. It is only on the one side, as I think you can see in the photo. 

The second shows the bottom of the trunk where it meets the ground.

The third shows the entire tree as it is this spring. I hope you can see it against the background. Unfortunately I do not have a picture of the tree with leaves. 

Please let me know if you need further information. 

~ Christine


On Apr 26, 2026, at 5:06 PM, Ask Extension wrote:

The Question Asker Replied April 29, 2026, 12:00 PM EDT

I’m sorry Christine, there are no photos attached. Can you try again? Thanks!

MJ Replied April 29, 2026, 1:13 PM EDT

Christine if you have to, create a new question with the mountain ash photos and say this is a follow up to question #0199602 and is for MJ.

Thanks!

MJ Replied April 30, 2026, 10:31 AM EDT
I’m sorry. I can’t imagine why the pictures didn’t attach. I am trying again with fingers crossed. 

On Apr 29, 2026, at 12:13 PM, Ask Extension wrote:

The Question Asker Replied May 01, 2026, 12:30 PM EDT

Hi Christine,

Still no photos! I’ll list some possible problems that could be holding back your tree.

You said the tree has hardly grown in five years. Are all the branches alive? When the tree leafs out is the canopy full, or does it look thin? Recent years of drought and winters without reliable snow cover have killed or damaged trees in Minnesota through root damage. Make sure this tree is regularly watered in dry times and right up until the ground freezes.

Even if the deer damage doesn’t go all the way around the trunk, if the scrape is extensive it can inhibit movement of nutrients and water up and down the trunk.

I wonder if the tree was planted at the proper depth. Planting a tree too deeply can damage and eventually kill trees. You should see a slight swelling of the trunk at ground level where the roots flare out before entering the soil. If the tree is planted too deep it may eventually strangle itself. See this website and the link to girdling roots:

https://extension.umd.edu/resource/trees-planted-too-deeply/

Stop the tree spikes. Fertilizing a stressed tree is counterproductive.

See the links on this page for possible problems:

https://trees.umn.edu/showy-mountain-ash-sorbus-decora

This page shows some of the problems that mountain ashes can develop.

https://apps.extension.umn.edu/garden/diagnose/plant/deciduous/mountainash/index.html

I feel like I’ve tossed a bunch of information your way without knowing if any of it will help! If this tree is important to you, get a certified arborist to come to your property to look at the tree. Make sure they’re an arborist, not just a guy from a tree company. If the tree was planted too deep and isn't too damaged they may be able to excavate around the tree to expose the top roots. Often this is done with blasts of water.

I hope this helps. Sorry about the photo issue. Good luck.


MJ Replied May 01, 2026, 3:25 PM EDT

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