Jobbyj
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New Chinese Elm - Help - Black Leaf Spot...?

Help!

I have had a Cinhese Elm for the past month. I got it on the first of may for my birthday and it was in good condition when it arrived. A few of the leaves were yellowing but was told that this wasn't something to worry about. After reading lots of info on caring for the little fella i placed him outside in my garden on the garden table. It gets a lot of light through the day and i have been watering regularly as soon as the soil goes dry to the touch. I water with plant food and tap water by soaking the soil till there is water flowing from the underneath. I then wait for 10 minutes and repeat the process. I water directly onto the soil. It has rained a few times though and now looking at the leaves some have started to develop black spots that look like slightly raised burn marks. The coverage is about 1 in 15 - 20 leaves at the moment (i don't have pictures at the moment but will try and get some) Having done some research i think that it might be black leaf spot. Help!

Also some tiny spiders made their home in the leaves and I removed them but was wondering if they might be detremental to the bonsai or not?

Thanks

JobbyJ

ynot
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Re: New Chinese Elm - Help - Black Leaf Spot...?

Jobby,

Welcome to the forum....
Jobbyj wrote:Help!

I have had a Cinhese Elm for the past month. I got it on the first of may for my birthday and it was in good condition when it arrived. A few of the leaves were yellowing but was told that this wasn't something to worry about. After reading lots of info on caring for the little fella I placed him outside in my garden on the garden table. It gets a lot of light through the day and I have been watering regularly as soon as the soil goes dry to the touch. I water with plant food and tap water by soaking the soil till there is water flowing from the underneath. I then wait for 10 minutes and repeat the process. I water directly onto the soil.
Ok, This all sounds pretty good except I am curious about the red bit above...

Do you mean simply the surface of the soil is dry or do you check deeper down in the soil where the trees roots actually live? Please clarify that for us. :)
It has rained a few times though and now looking at the leaves some have started to develop black spots that look like slightly raised burn marks. The coverage is about 1 in 15 - 20 leaves at the moment (I don't have pictures at the moment but will try and get some) Having done some research I think that it might be black leaf spot. Help!
Yes pictures please!... :)

Black spot only affects new growth that has not hardened off yet [As I am sure you are aware of from your research] This is what you have happening here correct? Daconil is one product often used on black spot as I understand it [Never had it].
Also some tiny spiders made their home in the leaves and I removed them but was wondering if they might be detremental to the bonsai or not?
Pictures please, Most of the kinds of spiders that spin webs are eating some of the things that can be bad for trees...lol. OR do you mean way way smaller - like spider mites - That's a different story.

ynot

Jobbyj
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Hi Ynot, thanks for your reply and your welcome.

I water when it is dry to the touch rather than testing deeper down. I press my finger gently into the top of the soil and if it is dry i water. But i am guessing from reading some of the other posts that it is better to test with a toothpick or something similar...?

As far as the research into black spot goes it has been very limited as i can't find much on the web specific to chinese elm bonsai. I'm at work at the moment so can't do anything about the picture but will try and get some sorted when i go home. As far as where the spot occur is concerned it seems to be uniform rather than just the new leaves.... I'm going on memory here so again might be best to wait till i get home. Is there something else that causes the black spots though. Some of the leaves don't necesarily have spots as such but look like someone has flicked black paint on them (it isn't black paint :D ) . At first i thought it might be sunburn spots cause it looks like a burn. There are no BBQ's or smokers or anywhere embers could have come from. Also a little bit of reading has shown that the black spots apear with white halos but there aren't any that display that characteristic...

[Edit - Just been doing some research in the lunch break. Is it possible that it could be Tar Spot]....

Tar pot
Scientific name: Rhytisma, a fungus
Species affected: Maples, particularly silver maple
Where it occurs: occurs primarily East River
Symptoms: After leaves attain full size, yellowish spots appear. These spots become raised, black, and tarlike by midseason.
Control Recommendations: Treatment is not recommended. However bordeaux (Bordeaux) applied at bud-break and 2 times 3 weeks apart may reduce infection.


Pictures are clearly what is needed.

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Jobbyj,

Black spot may be a bit of a misnomer as the infection is not necessarily circular but instead irregular in shape. It must be controlled or it will eventually kill your tree. Although younger leaves seem to be more susceptible older leaves can also show the effects of this fungus.

The first steps to take in the control of this disease is to remove the infected leaves so as not to further spread the fungus. Don't toss them on the ground but remove them from the growing area. Secondly, ensure that when you water you do not wet the foliage, this helps to spread the fungus also. I even have gone so far as to shelter mine from rain early in the season when the new growth is still tender and vulnerable.

Chinese Elms are reputed to be sensitive to some sprays but, on the advice of others, I have used the product Ynot mentioned with good results. Be aware that this fungicide will not "heal" leaves that are already effected but is intended as a preventative to inhibit the further spread of the disease. You may also have infected leaves that are not yet showing symptoms, Daconil will not cure these leaves either. In other words you may still see some new infections even after the fungicide is applied. With periodic applications you can control this disease successfully.

Norm

Jobbyj
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Thank-you to both of you for your help. I removed all the black leaves and have been looking for somewhere to buy Daconil in the UK but can't find it anywhere? Can you buy it online? The bonsai seemed to be doing better though after i cut the black leaves off but i have been noticing that green leaves have started to fall off....!! This isn't a good sign is it?!?!

Also, how do i get pictures on here?

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Jobbyj,
Thank-you to both of you for your help.
You're welcome, glad to help.
and (I) have been looking for somewhere to buy Daconil in the UK but can't find it anywhere? Can you buy it online?
Daconil is a brand name of the Ortho Co. The active ingredient is actually Chlorothalonil. There may be other products that may be effective but I know this one works. The copper solution known as Bordeaux may work but I can't vouch for it.
Also, how do I get pictures on here?


https://www.helpfulgardener.com/forum/viewtopic.php?t=3724

Norm

constantstaticx3
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I water with plant food and tap water
I'm wondering if the spots could be from the fertilizer. What strength is it? What brand? If it is necesary to water every day that might be too much fertilizer for it.


Tom

Jobbyj
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It could be...When i was bought the bonsai it was from an online shop and they sent it with a small bottle of Bonsai Food in a green bottle (not very descriptive i know, sorry). I water it with water and the food every now and then but it is possible that i am getting the water/food ratio wrong....Would this cause the black spots?

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Jobbyj,

It could be... ...Would this cause the black spots?
A few pictures would go a long way toward getting this sorted out.

Norm

Jobbyj
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I'm on the case! Sadly i have lost the cable to connect my camera to my computer. But i am getting another one. As soon as i do i'll upload tham. Thanks for watching this topic and check back soon.

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