chinese elm with frosting and yellowing of leaves

[mr_greggy]

Hi

I bought this Chinese Elm as a mallsai almost a month ago.
[img]https://i1213.photobucket.com/albums/cc462/mr_greggy/bonsai%20for%20forum%2015th%20July%202011/IMG_0942.jpg[/img]
(the pic actually shows its back, not front)

It has been doing great, growing many new leaves. However, in the last few days it's got me a little worried. Some of the leaves have been getting this "frosting", and even some of the new growth even has it from the start:
[img]https://i1213.photobucket.com/albums/cc462/mr_greggy/bonsai%20for%20forum%2015th%20July%202011/IMG_0943.jpg[/img]

This side of the tree is most affected:
[img]https://i1213.photobucket.com/albums/cc462/mr_greggy/bonsai%20for%20forum%2015th%20July%202011/IMG_0944.jpg[/img]

From my research I thought it might be mildew, but the pics I found don't match the pattern. Any help?

Also, a considerable amount of leaves are turning yellow, and after a while they will fall when touched. I think its losing at least 5 leaves a day. Here is a pic of 2 leaves which seem to be heading that way:
[img]https://i1213.photobucket.com/albums/cc462/mr_greggy/bonsai%20for%20forum%2015th%20July%202011/IMG_0945.jpg[/img]

This is another chinese elm that I bought with the other one. It looked a lot more bare, so it also seemed to be doing well, but its also affected by the same frosting and yellowing, tho to a lesser extent.
[img]https://i1213.photobucket.com/albums/cc462/mr_greggy/bonsai%20for%20forum%2015th%20July%202011/IMG_0946.jpg[/img]

I live in Malta, a hot mediterranean island, maxing round 35 celsius at the moment. I have them both outside, on top of a humidity tray and under a table, to protect them from the hot sun I figured (since they would get full sun otherwise - this way they only get a couplf hrs of direct morning sun). Here s a pic of the setup:
[img]https://i1213.photobucket.com/albums/cc462/mr_greggy/bonsai%20for%20forum%2015th%20July%202011/IMG_0958.jpg[/img]
(The one in the middle is a newer one I am trying to get identified on a different thread!)

I water them whenever they feel dry to 2cm deep, which is usually at least once a day. I try to do it in the morning, and avoid the afternoon, but sometimes have to do it late afternoon since they look extremely dry very quickly. I thought the soil might not drain well enough, but then again it seems to get bone dry so quickly. I'm kinda lost! Help please!

Thanks in advance!

Greg

PS - Any additional advice re styling, etc., is welcome

[TomM]

Hi Greg, Welcome to the forum for bonsai care.

I can not offer expert advice for you - being a world away from where you are. But in generality it is good to not panic with plant material that needs some time to adapt to its new home. Acclimation.

It sounds like you are giving good care, appropriate watering - considering the Summer heat in Malta. You might try giving some sort of shading though, like shade cloth or netting. I like the set-up you are showing. Nice group with humidity trays.

Please keep us informed with your progress.

[Fig3825]

Honestly, it looks like spidermites have attacked it. They thrive in warm, humid areas. Sitting on a humidity tray indicates to me that they get plenty of humidity and at 35C...

Take a look at the underside of the leaves and see if you have tiny spider-like insects crawling around. Another way to check is to mist the plant and see if there are small webs at the base of the leaves.

Initially, you won't find many, but eventually they will kill the entire plant if left unchecked.

The only reason I am thinking this is what you MIGHT be experiencing is because I am raising a dwarf meyer lemon tree and I had it indoors over the winter in a controlled environment that stayed around 80 degrees and sometimes higher, had an average humidity of around 70 and was kept under a 400w MH lamp. Almost the exact same look as when my meyer was attacked by them. Also lost the leaves they had damaged.

Let me know if you find this is the culprit and I can provide some more resources for you.

[Fig3825]

Forgot to mention they are just barely visible to the human eye and there are two main types. Red ones and ones that are nearly transparent with two spots on their back. The eggs look like tiny pearls on the underside of the leaf. You won't often see them on the tops of the leaves.

[mr_greggy]

Thanks Tom, thanks fig...

I have given ur advice much consideration. Tom, I have often wondered if my trees love the hot sun, as long as its only for a couple of hours and not afternoon sun, or if it is too hot at this time of year here for a chinese elm. My middle one I still have not identified, so that leaves me even more in the dark. (There is better pics of it in a separate thread in the 'identification' thread, if you could take a look...) I am considering putting up some sort of screen that will somewhat filter the hot sun...

Fig, I looked at pics of spidermite injury and it does look terribly familiar. I just checked for them but could not see any with my naked eye. Its too hot for me to mist them at the moment, but I will later, and try to get hold of magnifying glass to take a better look.

Thanks again for ur contributions guys. I have been fascinated by bonsai for ever, but never grew a plant in my life, hehe. So I m feeling like a took a dip in the deep end here

Much obliged...

Greg

[Fig3825]

With that much damage, I think if you had the spider mites, you would see them with the naked eye. So I'd guess that that is not your problem. They move around a lot and while tiny, you'd still see them.

[Gnome]

mr_greggy,

My initial reaction was also that it was some sort of insect damage. The leaves are similar to the damage I see on Azaleas that is caused by Lacewing.

https://2.bp.blogspot.com/_lLPntiI05bc/S4aOVy2a_II/AAAAAAAAAEE/sNageAtueOg/s320/azalea_lace_bug_04.jpg

BTW, it's not always easy to spot insects so look carefully and don't rush. They may even be gone already.

Norm

[mr_greggy]

Cheers Norm! Hopefully they're gone already like you mentioned! I've been spending a lot of quality time with them, and I really couldnt spot any bugs. I guess I'll see if it continues to affect other leaves...

About the yellowing and falling off, is it normal for a tree to lose 5-10 leaves a day? Do you think it might be solved by shading like TomM suggested? That was my next planned modification to the setup

And one last thing - any idea what kind of tree the little one is? I am just treating it like the Chinese Elms, even tho it's surely not. I put up close up pics on the Identification thread.

Thanks for your invaluable advice guys...

G

[Gnome]

mr_greggy,

Chinese Elms can behave like evergreens depending upon the environment they are living in. If the tree had not been allowed a dormancy this past winter then it is possible that it is simply shedding older leaves as necessary. In other words, even evergreens shed their old leaves eventually.

Concentrate on the overall health of the tree rather than a few yellowing leaves. If the new leaves are healthy and unaffected by the, presumed, insect damage then you are probably OK.

Norm

[mr_greggy]

Thanks for your reply Norm.

Yeah, I ll take your advice and not fuss too much about it then Re: the 'not allowed dormancy last winter' theory, I don't think thats the case, as even new tiny leaves sometimes yellow and fall, but anyway. Our winters nights here only go down to 5-8 celsius (41-47 F)... so do you think that will be enough to give it dormancy?

I also have a little sweet plum (or that's the best guess I've been able to get about its id anyway). Do you think that might be better off indoors, since I've read it might be sensitive to extreme heat (its currently maxing 35C/95F here, and could go up to 41C/106F). In that case, do I put it back outdoors when it gets cooler, especially for dormancy?

Cheers,

Greg

[Gnome]

mr_greggy,

Re: the 'not allowed dormancy last winter' theory, I don't think thats the case, as even new tiny leaves sometimes yellow and fall, but anyway.

Sometimes a few leaves seem to yellow for no apparent reason, so again, play it by ear and don't worry too much over a few leaves. If you note an overall decline then that is a different matter.

Chinese Elms are also susceptible to a disease known as black spot fungus. I have one tree that gets it so bad I cannot seem to manage it while other Chinese Elms seem almost unaffected. Do you note any black lesions on the leaves?

Our winters nights here only go down to 5-8 celsius (41-47 F)... so do you think that will be enough to give it dormancy?

Thanks for providing the F. temps, try as I might C. does not come naturally to me.
That range will likely be too warm to force a Chinese Elm into full dormancy but that should not be a problem. These trees have a wide distribution in nature and can behave like an evergreen or a deciduous tree depending upon their environment. This is what makes it possible, if not ideal, to keep them as indoor trees. So while the rest period will be beneficial for it, don't be surprised if it holds onto its leaves until next spring. The old leaves will fall as new ones come in.

I also have a little sweet plum (or that's the best guess I've been able to get about its id anyway). Do you think that might be better off indoors, since I've read it might be sensitive to extreme heat (its currently maxing 35C/95F here, and could go up to 41C/106F). In that case, do I put it back outdoors when it gets cooler, especially for dormancy?

Sorry, I can't help at all with this species.

Norm

[mr_greggy]

Thanks as always Norm.

That range will likely be too warm to force a Chinese Elm into full dormancy but that should not be a problem. These trees have a wide distribution in nature and can behave like an evergreen or a deciduous tree depending upon their environment. This is what makes it possible, if not ideal, to keep them as indoor trees. So while the rest period will be beneficial for it, don't be surprised if it holds onto its leaves until next spring. The old leaves will fall as new ones come in.

So does that mean that, even if it doesnt go into full dormancy, it will still get a good rest from being left outside for 40F's? I originally wanted to get a bonsai for indoors (like most bonsai beginners I guess), but read from many who warn against this, quoting problems like increased disease/pests and exhaustion from lack of dormancy. I had resigned to perhaps only bringing it in for fall, if at all. But maybe outdoors is a bit too hot for it right now too? Do I just take it out for the winter then? This always confused me, as there s much contradictory advice out there...

Greg

[Gnome]

mr_greggy,

So does that mean that, even if it doesnt go into full dormancy, it will still get a good rest from being left outside for 40F's?

Yes, I think that should be fine but since my climate is different I don't speak from experience.

I originally wanted to get a bonsai for indoors (like most bonsai beginners I guess), but read from many who warn against this, quoting problems like increased disease/pests and exhaustion from lack of dormancy.

Chinese Elms don't have the same strong requirement for a dormant period as some other species do but I agree that outside is better for them. I once brought one inside around New Years. This allowed it a brief dormancy and it did fine until spring when it went back outside. I have never tried to keep one inside full time.

I had resigned to perhaps only bringing it in for fall, if at all. But maybe outdoors is a bit too hot for it right now too? Do I just take it out for the winter then? This always confused me, as there s much contradictory advice out there...

Since my climate is so different I really don't know what to suggest other than to let the tree guide you. If it is doing OK outside now why bring it in? Have you looked into shade cloth?

Norm

[mr_greggy]

Thanks norm.

I ll try to resist the tempation to bring it in as much as possible. But if I do fall for it, I guess I ll make sure it is back outdoors for January and February, since those are the only 2 months with coldish temps. Hopefully that will give the best chance to sleep for a couple of months.

I havent looked into the shading cloth yet, partly because putting a couple of deck chairs to protect it from early afternoon sun seems to have reduced the yellowing/falling, and partly because I been kinda busy with my pomegranate project (see the other thread in this same forum - your critique would be very much appreciated). I ll consider the shading cloth if I get more yellowing/falling.

Out!

Greg

[mr_greggy]

Hi guys,

More updates from my chinese elms. Mainly about the top one in the pics above.

Many leaves are still drying out, but many new ones are comin out. Some of the new leaf buds seem to dry out before they re out - some when they re still little green dots, others when they start opening up from a bud into tiny leaves. I was wondering whether this and the drying out could be related to being root bound. When I bought them, I repotted them right away, but I had no idea what I was doing. I later realised they were in need to root pruning, since at least one of them had roots coiling up around the edge of the pot. Since then I have not repotted them, hoping they would be ok until the beginning of next spring, figuring that would be a better time to repot and root prune. Any thoughts on that?

I still havent tried the shade cloth. I guess mainly because I don't think they re getting all that much direct sun. I figure that if anything, it is the intense heat that might be burning them, and not the light (the 95F maxes I spoke about are shade readings, not in the sun).

Hope you guys are having a good summer!

Greg

[froggy]

The images first reminded me of spider mite damage on my lemons as well... But I got myself an elm (Jacqueline hillier) and had it right along with the infected lemon trees and it didn't get touched...(plenty of yummy citrus around) Anyways, it lost some leaves upon arrival & repotting, but it is growing strong now. Temperatures here were comparable for the last few weeks, but my plants only get sun after about 2pm, and even then it's mostly filtered by large trees...
Oh and I finally got rid of them mites too

P.S. If you're checking for mites, try swabbing the undersides of some leaves with a q-tip - elm leaves are tiny, but a mite or two might stick...

[mr_greggy]

Some of the new leaf buds seem to dry out before they re out - some when they re still little green dots, others when they start opening up from a bud into tiny leaves. I was wondering whether this and the drying out could be related to being root bound.

HELP HELP HELP!! My baby's losing a lot of leaves and I don't know how to save her!! Another thing which worries me a lot is the pot is not drying up. Is it not drinkin up any water a sign of it bein root bound? Sick? DEAD???

[kdodds]

This can actually be a sign of root rot. Pot bound trees generally take up moisture almost as quickly as it's added. Too hot or too cold and Elms will go semi-dormant or fully dormant, respectively. This is one reason we should never water to schedule, but as needed. The only thing you can possibly do now is to let the soil dry almost completely before rewatering.

[mr_greggy]

I was thinkin it might be going dormant due to the heat, but if its not already root rotting, I think I'm definitely risking it since its not drinkin the water. Guess I can try such some moisture up with kitchen roll and taking it out of the moisture tray, right? I sure hope its not rotting arleady!! I would have managed to kill the hardy chinese elm...

[Kicks]

I have a Chinese elm in the Mohave desert, it loves the sun but I do keep it protected to limit it's direct sunlight to about 2-3 hrs early in the day. I mist the tree early in the morning because otherwise I do get some drying of leaves/buds but take heart, it's like 110f here every day all summer & my tee has grown like crazy! I'm sure you'll get yours figured out. Also I keep a chopstick in the dirt & only water it when the chopstick is dry. Mine even had scale bugs and some aphids this spring but I got rid of those too and the tree perked right up.