Troubleshoot this dead Chinese Elm with me!

[cheap_walmart_art]

I am seeing good bud movement on all of my overwintered trees except for this Chinese Elm. A small scratch test indicated this guy is dead or soon to be, but I'll let it linger on to see. Also some crazy bark peeling out of nowhere. Would love some opinions as to what may have happened here.

Here is some background.

Acquired fall 2017 overwintered outside in mulch bed.

Repotted and root pruned spring 2018

Overwintered outside in mulch bed 2018

Basic pruning and shaping through 2019, wintered in same mulch bed.

Soil is DE, pumice, lava. It's been fertilized during the growing seasons with cottonseed meal and kelp power at 9:1 ratio. During the summer I kept a top dressing of sphagnum moss to cool the pot, removed for overwintering.



Here it is in July 2019



Here it is today, with some detail shots of the split bark.

 

[penumbra]

That is a mystery. Is it a regular Chinese Elm or a cultivar?
Consider that although it was a very mild winter it was also a dry winter, at least here in NW VA.

 

[rockm]

Are those stones on the soil surface part of the soil mix?

Pulling the tree out of the pot to look at the roots is more instructive about what killed this than looking at peeling bark...

 

[cheap_walmart_art]

That is a mystery. Is it a regular Chinese Elm or a cultivar?
Consider that although it was a very mild winter it was also a dry winter, at least here in NW VA.

I'm not really sure on the cultivar - was a basic S shape picked up at a box store. Winter here was mild with a few really cold nights, but it was very wet.

Are those stones on the soil surface part of the soil mix?

Pulling the tree out of the pot to look at the roots is more instructive about what killed this than looking at peeling bark...

Rock - Those stones are part of the mix. I think this mix was the Bonsai Jack universal mix now that Im looking at it closer. Those may be the "Bonsai block" particles - calcined clay. Took your advice and pulled it from the pot and the roots look...ok. Even looks like some new growth happening, so maybe its not all the way dead?

 

[Zach Smith]

Sometimes trees die for no discernible reason. But that looks like a lot of roots without much soil. Did you prune away enough roots in 2018? Sometimes trees will grow so many roots in the interior of the root mass that it doesn't take anything for dryness to set in and harm or kill the tree - even if you water regularly and the surface seems good and moist.

 

[rockm]

Dry root masses in winter can be a killer. If you had a few nights overwintering this below 25 or so, and the roots were dry, might explain. There look to be some live roots in there, so I expect this might resprout from the base. The top looks completely dead though.

 

[cheap_walmart_art]

I will let it linger on a bit and see what happens as we get into spring. I am surprised if drying out was the issue as we had weekly rain almost all winter, but definitely not out of the realm of possibility.

Thanks for the discussion, I always like to try to pinpoint what the issue may be when I get a dead tree so as to not repeat my mistakes. In this case, I'm thinking better water monitoring during the winter despite wet conditions will be my takeaway. (just a note, I have several Chinese elm seedlings in 4" pots that were heeled in next to this tree and they have all woken up healthy.)

 

[cbroad]

@cheap_walmart_art
I think you've got good advice so far.

From the last pic in your first post, the cambium under the exfoliating bark doesn't look dead in my opinion. I have had plants that aren't supposed to exfoliate their bark, exfoliate bark. I have noticed in years of very good growth that that explosive growth has caused fissures in the bark, which eventually peels away to expose the newer cambium.

Have you tried scratching the yellowish-beige cambium?

I'll admit no buds popping yet is a bad sign.

Your tree may have had horrible growth for a couple years before you rescued it from the shelves, then all of a sudden it was receiving proper care and exploded with growth and it could now be shedding off it's older bark.

I agree that your roots look relatively healthy. Don't give up on it yet, good luck!

 

[Wires_Guy_wires]

Yeah, I'd scratch that layer under the bark too, it looks alive. It looks like the buds that are there, still hold moisture. They're not wrinkled or dessicated as far as I can tell. I would suspect those to be the first to die off if it's dessicated.
Healthy root growth too.

I think it's faking it.

 

[just.wing.it]

think it's faking it.

Maybe doing the old Lazarus trick....
Good luck!

 

[Mike Corazzi]

Put it back indoors where it looked happy.






...kidding