European hornbeam failing again

Question: I have tried to grow a European Hornbeam on the side of my patio several times but the tree in this location doesn't seem to thrive. I planted three of them beside our patio, two of them are tremendous trees. I had Arborscape come to look at the one tree that was not thriving. They didn't know what was wrong with it but gave it a liquid that has beneficial microbes. It still didn't thrive by the next year. They advised taking it out and said that another young european hornbeam I had planted in another location and was having 2nd thoughts about its location could be moved to the patio spot. I think it had been in the location maybe 9 months, give or take. My gardener moved the tree a year and a half ago. I didn't see how carefully he transplanted the tree. I mulched and watered it regularly. Last year, the first spring after being transplanted, the tree struggled. The leaves were small and eventually looked shriveled. I thought maybe it had transplant shock and decided to give it another season. I mulched it during the winter. This year it looks like it is continuing to struggle. The leaves are small, paler than the other hornbeams of various ages I have, and leaves are smaller. I now notice some are yellowing. Any ideas about what is going on? I haven't tested the soil for anything. In the photo, the darker, larger tree next to it is the same species.

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied June 17, 2024, 8:45 PM EDT
response: When plants seem to fail in a location, the reason might never be clear. Soil testing is a general panel, or specific things can be tested. But when you don’t have an idea of what to test for, it’s a challenge. Please provide a photo or two from further away, maybe a couple of angles. Guesses are things like pipe breaks: Irrigation? Water supply? Sewer? Gutter drains? What might be buried there? Was a big stump from a prior tree left in place and buried with a few feet of soil? Any clues from construction of the retaining wall and patio? How deep can you probe and find nothing? Are any utilities located here? Possibly the photos will suggest other lines of inquiry.

responder: The Question Asker Replied June 18, 2024, 11:46 AM EDT
response: Hi Jacki! This is very helpful! There is probably a gas line below and maybe other things. I'm going to call for a utility locator and check our gas bills. I'll send more pictures when I get a chance to take more. Best,JanetOn Mon, Jun 17, 2024, 5:45 PM Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied June 21, 2024, 12:20 AM EDT
response: Hi, Jacki: I've attached a few more pictures further away, as you requested. Let me know if you can't open any of them.  Let me know if you have any further insights as a result.  Best,  Janet  20240619_094748.jpg   20240619_094815.jpg   20240619_094825.jpg   20240619_094901.jpg    On Tue, Jun 18, 2024 at 8:41 AM Janet Bauer <<personal data hidden>> wrote:  Hi Jacki! This is very helpful! There is probably a gas line below and maybe other things. I'm going to call for a utility locator and check our gas bills. I'll send more pictures when I get a chance to take more.  Best,  Janet   On Mon, Jun 17, 2024, 5:45 PM Ask Extension <<personal data hidden>> wrote:

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied June 21, 2024, 2:47 PM EDT
response: I please attach directly if I can’t get them pulled in via Google drive.

responder: The Question Asker Replied June 21, 2024, 6:27 PM EDT
response: On Fri, Jun 21, 2024 at 3:26 PM Janet Bauer <<personal data hidden>> wrote:  Hi, Jacki: Please see attached. I'm sending in 2 batches so they aren't converted to drive links.  Janet   On Fri, Jun 21, 2024 at 11:47 AM Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied June 21, 2024, 6:27 PM EDT
response: Hi, Jacki:  Please see attached. I'm sending in 2 batches so they aren't converted to drive links.  Janet   On Fri, Jun 21, 2024 at 11:47 AM Ask Extension <<personal data hidden>> wrote:

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied June 22, 2024, 3:01 PM EDT
response: I was able to see the photos. Thanks. No clear answers that I can see. Some thoughts: The other trees and shrubs are quite established, and roots reach much further than the plant canopy “drip line”, so root competition might be an issue. Your location is a bit of a raised bed, with concrete on three sides and a big tree & shrubs on the other. I don’t know of any way to solve this except grow smaller compatible plants. Failure to establish roots into native soil is a primary reason new trees fail. This can be due to a number of reasons. Sometimes the tree is planted too deeply. Roots need access to air, and grow in top few inches of soil. Sometimes the planting hole was amended with something. Only native soil should be put back with the tree roots. This is because water doesn’t flow well between different soil textures, so roots don’t, either. This can mean roots grow in circles, eventually girdling the tree. It can also mean you water the root ball but water isn’t reaching beyond the planting hole, or you are watering the area, but water isn’t moving into the rootball. You need to water and then check the soil to see that you are getting the amount of water to the right places. This often means checking with a trowel, your fingers, or a screwdriver (it goes into wet soil easily, and won’t into dry). Check the trunk, is it healthy? I see some checking, but can’t tell if it’s an issue. Planting on a slope is tricky, and you didn’t watch how it was done. Perhaps the hole wasn’t wide, which is another reason roots struggle to reach out. A slope is also a challenge to water well. A “moat” around the roots of a new tree is recommended to allow water to soak in well. It’s hard to do on a slope. I suppose if it was my landscape, I would make a bit of a terrace and plant the smallest tree I could. The terrace would hold water a bit, and a small tree would have time to grow roots into the surrounding roots before it got too big and required more soil. There might be utilities that make the soil there extra-shallow. I’m glad you are asking about that. Here is EC 1438, OSU’s basic new tree guide, referencing planting holes and watering concepts. I’ve seen privacy screens and sun sails suggested for use while new trees or shrubs fill in. A planter box with trellis for a vine can be used also. I’m sorry I can’t offer a more conclusive diagnosis.

responder: The Question Asker Replied June 22, 2024, 11:37 PM EDT
response: Thank you for all these thoughts. We are having the utilitiesocated and I'll do some probing after that.  Thanks again.  Janet   On Sat, Jun 22, 2024, 3:01 PM Ask Extension <<personal data hidden>> wrote: