Deciduous Leaf Curl Fungus Disease

[Bretts]

Been meaning to start a general thread about this disease and te trouble it has caused this season but always have trouble knowing where to start.
Guess a list of trees I know of being affected will be a good start.

Acer buergerianum (Trident Maple), Acer palmatum (japanese Maple), Acer ginnala (Amur Maple), Acer griseum (Paper bark Maple), Carpinus (hornbeam), Robinia, Fraxinus (Ash), Quercus (oak), Privet, Crataegus (hawthorn), Prunus.

[Mojo Moyogi]

Hi Brett,
How does this sound : http://extensionhorticulture.unl.edu/Cu ... Curl.shtml,

If it is Peach Leaf Curl, It is very easy to cure.

Cheers,
Mojo Moyogi

[Bretts]

Don't think so Mojo Moyogi.
It's probably Anthracnose or Phyllosticta and Septoria or something similar.
This is the best general description of the possible Fungi.
https://www.utextension.utk.edu/publicat ... /SP546.pdf

Here is one on Anthracnose
https://www.na.fs.fed.us/spfo/pubs/fidls ... idl-ae.htm

Also here are a couple of threads started by Mela on the same issue
viewtopic.php?f=19&t=456
viewtopic.php?f=19&t=3198

[Jamie]

maybe you could select the important bits from the posts about the trident curl and qoute them or copy them into this thread and the cure you have found for trident

[63pmp]

My thoughts are that most pathogens are opportunistic (certainly there are plenty that are extremely deadly, eg dutch elm disease) but in the main, most of these anthracnose type molds are opportunistic and looking to attack weaker plants.

I notice a real difference between the health and vigor of field grown trees compared to pot grown plants. Even trees in big grow pots don't grow as well as field plants. And everyone knows if you want a tree to put on weight, then plant it out in the ground. My thoughts are that the plants in pots don't get the same level of nutrition. Nutrient deficiency being one of the important aspects, oxygen and water deficiency another. The thing with nutrient deficiencies is often they go unnoticed, the so called "hidden hunger". For example, it is known that potassium deficiency causes the cuticle on leaves not to form properly, this has a serious effect on the protective surface of the leaf, yet the plant still grows, getting the K it needs from older leaves. Another example is excessive nitrogen application produces leaves prone to fungal attacks.

I think controlling these diseases is a lot about horticultural practices, not so much about killer pathogens.

Paul

[AnneK]

This may take the subject slightly away from BrettS original request But I like Paul's opinion on this. —If only the trees could talk to us!

I have two problem trees. 1) A Trident which has for some time had a virus condition, the leaves having very fine spots and slightly mottled and wrinkly. And 2). A PJ which I am looking after and it came with a sluggish disposition and variegated leaves. I have been trying with sufficient success, that I now intend to increase the applications from monthly to fortnightly. The product is called GT Silica from Growth Technologies. It is supposed to help the uptake of nutrients. I hope this helps the forum. Also I picked up the info when talking to GT that the Aussie who makes violins may know something of this product in relation to bonsai, if he is in the forum.

Regards, AnneK.

My thoughts are that most pathogens are opportunistic (certainly there are plenty that are extremely deadly, eg dutch elm disease) but in the main, most of these anthracnose type molds are opportunistic and looking to attack weaker plants.

I notice a real difference between the health and vigor of field grown trees compared to pot grown plants. Even trees in big grow pots don't grow as well as field plants. And everyone knows if you want a tree to put on weight, then plant it out in the ground. My thoughts are that the plants in pots don't get the same level of nutrition. Nutrient deficiency being one of the important aspects, oxygen and water deficiency another. The thing with nutrient deficiencies is often they go unnoticed, the so called "hidden hunger". For example, it is known that potassium deficiency causes the cuticle on leaves not to form properly, this has a serious effect on the protective surface of the leaf, yet the plant still grows, getting the K it needs from older leaves. Another example is excessive nitrogen application produces leaves prone to fungal attacks.

I think controlling these diseases is a lot about horticultural practices, not so much about killer pathogens.

Paul

[Mojo Moyogi]

I think controlling these diseases is a lot about horticultural practices, not so much about killer pathogens.

Paul, that is one of the most common sense suggestions put forward.

Disagree??

Let me grab the whiteboard, and play Dr Gregory House for a minute.

Symptoms are:
Leaf Curling/Distorted leaves

Some of the many theoretical causes suggested in 3 different threads:

Anthracnose
Phyllosticia
Septoria
Something similar
Bug infestation of some sort
Virus
Root bound
Poor soil
Sun damage
Verticulum wilt
Small aphids
A root issue
Leaf burn
Leaf burn that comes and goes
Don Burke's leaf eating pest at night
Ray Nesci's insect pest with an Eco Neem or Confidor cure
Too much water
Mineral deficiency
Over fertilisation
Thrips
Leaf Curl treatable with lime sulphur
Wind agrivated infection
Fungal disease cured by Yates Bravo
Thrips and Fungus together
Root rot
Soil borne pathogen
NSW climate thing
Pathology report fungal issue with Thrips

Is there anything in this comprehensive list of what it could be, but what it is not, that could be rubbed off the diagnostic whiteboard? Look at the evidence.

Cheers
Mojo Moyogi

[Bretts]

[Bretts]

Paul there is some good advice in there but the problem is that you still seem to insinuate that anyone affected by this must be doing something drastically wrong. Off course the health of the tree will affect the severity of the attack but as I have shown you healthy full sized trees in the ground have also been affected by this. In fact I saw a street (ash) tree the other day that looked so bad from a leaf curl fungus(can only guess is the same one) that I would not be surprised it does not make it through the Winter. Maybe it is also a bit weak from the drought. The fact is this can and does kill. We all should know that trees in pots are more susceptible to their environment than full sized trees in the ground.
So limiting the stress a potted tree by getting everything just right will help in the first instance in resistance to infection(compost tea sounds great for this) as well as severity of the disease if infection occurs. Yet if it was that simple then bonsai masters would not bother using winter fungal prevention.

A bonsai tree can take a joke but when I have had a number cared for trees cark it just because they where defoliated I can sadly call this fungus a killer and don't appreciate being told it is not.
I am really a little tired of trying to prove that an issue that is being faced by a variety of bonsai people on the east coast is actually a dam bugger of an issue.
I have seen collections that have grown happy for years. This year it looks like a considerable number of specimen trees will not make it through the Winter.

AnneK the trees are talking and we can only do our best to try and understand them

That's an interesting product. There are a few things that will help in the uptake of nutrients. Usually it is a soil conditioner that works with the microbes in the soil. Will have to look into this and seeif that is what is happening.

[63pmp]

Not drastically wrong, just a little wrong.

If you really want to know what it is, spend the bucks and get the sucker ID’d.

http://www.dpi.nsw.gov.au/aboutus/servi ... s-diseases

Paul

[Bretts]

That doesn't answer any of the questions Paul. Were the Elms wiped out by dutch elm disease because they where a little wrong in their care. Funny I recall that it was not prejudiced against well cared for bonsai or feature trees in well cared for Parks?
Kinda puts your theory on it's arse Even the experts could not stop it wiring out almost every tree.

[63pmp]

be really good if you'd read an entire post; not just he bits that get up your nose.

Covered the DED bit, read the post again. And yes, even park trees get stressed eg Sydney Hyde Park fig problem, which involved the placement of about 10 million dollars worth of new drainage.

Paul

[Bretts]

If you read all the post why do you only answer the bits you want to. If it was only a matter of care why do we Dormant treat our bonsai for fungus to prevent it.
As I got no answer I will answer this for you. It is not just an unhealthy tree that can be affected. it can also be other factors such as a high concentration of the pathogen together with a low concentration of the combating pathogen. Once the pathogen gets hold it weakens the tree and the fungus gradually gets the upper hand.
Brent waltson talks of a fungus that kept wiping out his cuttings. Top notch nurseryman but with the help of all manner of experts he could not get rid of it for years. Then he worked out the cuttings could take a higher temp than the fungus.
We can not control everything and some times the environment is working against us and in favour of the disease.

There are varying degrees of nasty when it comes to pathogens. Such as Dutch elm disease and Die back. Then there are ones that are not so nasty such as Powdery Mildew in any sense there must then be a number of diseases in between this nasty scale.

[Mojo Moyogi]

Brett, you really need to start taking in information, without giving it out for a while. You have openly dismissed potential cures, treatments and general advice that has been provided in good faith, that have not been to you liking, or that clash with your theories. Is there any chance that these trees could stop being buggered with, defloiated, poked at and sprayed with god knows what on a whim? I think that the tail has wagged the dog for too long on this, there has been plenty of human intervention with this issue that may well of worsened or in the least prolonged the effects of this "disease".

Mojo Moyogi

[Bretts]

I have taken all the information available and have also acted on it. I have dismissed no potential cure in fact I have looked into tried and documented every one of them on the forum. I have sprayed and defoliated from advice in experimental conditions I have done nothing on a whim but only followed advice I was given. This advice has been from some of the best in our country and abroad. Why should I be concerned about your weird rant.
Your suggestion of Peach Leaf Curl is about as far from the mark as we have been so I would say it is you that needs to look at the advice given.