Curious frost effect

[Botanicus]

This is a leaf of Livistona saribus shortly after a heavy frost, the leaf looks damaged as if the tissue was frozen. Yet by later the same day these spots disappear and the leaves are green and healthy looking. Anyone have an idea as to whats happening here?

[Botanicus]

Same tree later that day.

[TexasColdHardyPalms]

Unfortunately i see that every year on palms here during winter.

[Umbrae]

Happens on occasion to my copernicia sometimes ...

[rsproule]

 

 

This is a post I did a few years ago in the same issue.:

 

Re: Temporary Dark Blotches after Freeze.

Regarding the observation that even cold hardy palms will get temporary dark blotches on their leaves after a freeze:

Dick I think your theory about this is correct. I did some research on the web about this. I did not find any one article that exactly explained, but I came away with the following impression:

When freezing temperatures are reached water in the cell protoplasm (cell juice) exits the cells and accumulates in the intracellular spaces inside the leaf. This defense mechanism prevents the inside of the cells from freezing (and subsequently bursting) by concentrating solutes within the protoplast thus depressing the freezing point by 4 to 6F. The water that accumulates in the intracellular spaces can freeze for a short time without necessarily damaging or killing the plant cells. The water in the intracellular spaces causes of the appearance of the dark blotches on the exterior of the leaf. 

The protoplasm remaining inside the cells now has much lower water content and the cells are dehydrated. If the cell is not able to re-hydrate itself it will eventually die. The intra-cellular water is probably reabsorbed into the cells via osmosis. When the water is reabsorbed the dark splotches disappear. Presumably freeze tolerant plants are better adapted to this two-way water exchange and are able to more efficiently re-hydrate their dissected cells. This would explain why the dark splotches on a very cold hardy palm like a Canary disappear very quickly where as the same blotches on less cold hardy palms can take days to disappear.

I don’t know if the above info is correct, but it’s a summary of what I quickly gleaned from various articles on the web. If anyone can confirm this explanation that would be great. To research this yourself search on the following key words: plant, cell, protoplasm, damage, freeze, and dehydration

[Botanicus]

Thanks for the replies, the above explanation sounds plausible, and I was unaware of the same effect on other palms. 

[Phoenikakias]

The german equivalent term is "Verglasung".

Could you please help me locate those old posts?

Edited May 24, 2017 by Phoenikakias

[Phoenikakias]

12 hours ago, Umbrae said:

Happens on occasion to my copernicia sometimes ...

I am very glad that Copernicia (which sp or spp in particular?) posess this kind of defense mechanism against frost.

[Pal Meir]

3 hours ago, Phoenikakias said:

The german equivalent term is "Verglasung".

Could you please help me locate those old posts?

"Verglasung" means vitrification, here in plants.

[Umbrae]

Alba and prunifera

[Phoenikakias]

1 hour ago, Pal Meir said:

"Verglasung" means vitrification, here in plants.

Pal I know, I have such translated to Eglish this german word in the EPS. Nevertheless how come have been used this  descriptive word for this kind of process?

[Pal Meir]

44 minutes ago, Phoenikakias said:

Pal I know, I have such translated to Eglish this german word in the EPS. Nevertheless how come have been used this  descriptive word for this kind of process?

Because it is like a solid liquid (= glas), not with the internal structure of a crystal.