Ulmus Parvifolia affected by frost

[wojt333]

Hello all,

Another post of the same tree:
For about a week it has been very cold for Dutch standards, with night temperatures as low as -15 *C locally.
Besides that, a good amount of snow has fallen.

Once the temperatures dropped below -4 / -5 *C, I've moved my deciduous trees into a shed, out of the wind.
Also, I wrapped all the pots in "bubble foil"
This shed is unheated and the temperatures inside dropped lower than I expected.
For some of my trees ice crystals formed between the soil particles. (mostly on the top layer)

As most of my deciduous trees lost their leaves, I cannot see what the impact of these temperatures has been until spring arrives.
However, my Chinese elms haven't lost their leaves.
Yet after a couple of days in the shed, the leaves became vague instead of shiny.
Furthermore the leaves are hanging a bit, especially the recently opened buds.
The amount of light entering the shed is very limited, so this might play part since the trees hadn't lost their leaves.

Since the frost is gone now, I watered the trees thoroughly with cold water. (to ensure any remaining ice crystals would melt.)
Also I put the trees in a corner of the garden, out of the wind and direct sunlight.

What do you guys think?
Anyone experienced a similar case before?

See pictures of one of the cases:

Few days before the frost:





Few days after the frost:










Kind regards,

wojt333

 

[Forsoothe!]

What's done is done. I doubt it would kill the tree and it doesn't look dead, so just keep treating it like it's alive and see what happens, maybe not much.

 

[TomB]

Looks like you've got some frost damage on the newest growth there, and might get some dieback of the thinnest twigs. I wouldn't worry too much about it though, the leaves are likely to drop off and be replaced in the spring anyway. There may be more frost on the way, so keep an eye on the forecast and put it back in the shed if required.

 

[Forsoothe!]

By the way, the bubble wrap won't do anything. Insulation only delays temperature exchange and with a small object with very little mass there is essentially not enough mass to hold any heat. That's different from placing a tree on the ground or sinking a pot into the ground. The ground has great mass (density) and is a temperature and only has contact with the air temps at the interface. The mulch at some inches thick is a barrier that prevents the air from direct contact with the ground so that the ground does not change temp as quickly as it would without mulch. During daytime the sun radiates warmth into any object with direct rays including the mulch, offsetting the heat lost overnight, to some extent. In a garage, the whole garage and everything in it goes up and down day and night because it is mostly air, and air changes very quickly, like when a cloud passes overhead.

 

[Don Blackmond]

Hello all,
What do you guys think?
Anyone experienced a similar case before?
Kind regards,

wojt333

Chinese elms are weeds, and it takes a lot to kill them. Odds are you will see the leaves drop almost all at once, followed by fresh, lime green new growth.

 

[AaronVh]

I'm also from holland and i have similar conditions, except i have kept mine outdoors. Also a frozen pot, leaves look vague and the tree is still in leaves. Last year the tree dropped all the leaves around this time, but i wouldn't worry that much. As stated above; elms are hard to kill and the leaves will eventually drop, like it should.

 

[wojt333]

Also a frozen pot

I thought to have read that Chinese Elms are very susceptible to frozen roots, I believe in David Prescott's book.
But we'll see how the trees respond during the coming weeks.

 

[leatherback]

This one is fine. These do not drop their leaves untill they really cannot hold on to them. That is what you see now: It has deep frost and decided to drop some foliage. It might go bare. However, come spring, with will bud out again. My chinese elm looks like that every spring.

Mine stayed unprotected in an open shed, temps only a few degrees above air temps, which dropped to -15c a few nights in a row, daytimes around -10c. I checked mine last night, and I have tears in the bark, which might be problematic and the foliage is more brown than green. As such I would say yours will be fine. You will loose all the young growth though. I would avoid full midday sun untill you get good growth again.

 

[AaronVh]

I thought to have read that Chinese Elms are very susceptible to frozen roots, I believe in David Prescott's book.
But we'll see how the trees respond during the coming weeks.

I'm pretty sure that the soil was frozen for a few days, but not the roots. The ice actually protects the roots and works as an insulator (so i have read and heard). The roots probably won't survive the frozen soil for a long period of time, but that was not the case here. Only a few days. No worries here

 

[Oleg]

Elms don't like "wet roots" when it freezes, they die. Elms can take -30 C if they are buried (heeled) in the ground, that is in a pot in the ground not growing in the ground.

 

[wojt333]

I'm pretty sure that the soil was frozen for a few days, but not the roots. The ice actually protects the roots and works as an insulator (so i have read and heard). The roots probably won't survive the frozen soil for a long period of time, but that was not the case here. Only a few days. No worries here

I'm not sure if that's actually true. Since, per definition, the ice crystal are colder then the liquid water preserved in the soil particles. Therefore, when the ice particles are in direct contact with the liquid water, or air for that matter, it will lower the water's temperature. I'm not an expert on this, but I would assume that the more ice crystals in the pot, the faster the root system freezes.

 

[wojt333]

Elms don't like "wet roots" when it freezes, they die. Elms can take -30 C if they are buried (heeled) in the ground, that is in a pot in the ground not growing in the ground.

I have my trees under a cover during winter, due to heavy rains.
Barely watered them lately, so that shouldn't be a problem

 

[Sputnik 184]

My Chinese Elms were affected in the same way by the recent cold snap but now the dried up leaves are falling and already I can see an abundance of new budding. I would be surprised if yours doesn’t behave similarly.

 

[wojt333]

My Chinese Elms were affected in the same way by the recent cold snap but now the dried up leaves are falling and already I can see an abundance of new budding. I would be surprised if yours doesn’t behave similarly.

I'm glad to hear yours is budding already! Hope mine will respond in the same manner!