Please help identify a "persistant" leaf problem: mineral, roots, fungus?

It appears Daconil fungicide also contains the active ingredient chlorothalonil mentioned above in Bravo fungicide. An unsavory chemical to be sure, but what else to do? The Wikipedia description of Leaf Curl Fungus as mentioned in Bretts link does not really seem to match my disease symptoms either, as there is no whitish bloom on the leaves at any point in the progression.

I'd wager that it is not a leaf fungus. If it is Verticillum wilt, there is no treatment.

Heat will do amazing things to Japanese maples. It is NOT the heat on the leaves that is the problem. It is heat in and on the pot. Ceramic pots are heat sinks, and if the pot is a darker color they're even worse. Get your trees in the shade. If that's impossible, wrap pots in foil or white material of some sort. This is why plants in the ground are not as badly affected.

With the upper 90s temps we've been having here, some unglazed brown pots are almost too warm to carry comfortably if they've been sitting in the sun.

Water does not cool them down. In fact, water once it is warmed by the sun retains heat for a very long time.

I don't really think it is a leaf fungus either, but rather a systemic one, like verticillium. Again, the weather has been hot, but not so much more than other periods. My maples are in the shade. I brought my more affected palmatums inside the cooler house during the wave of heat last week. They continue to decline. My first encounter was last August when it was cool and damp. I don't know, just saying. Hope to know someday. Keep hoping someone will positively ID it.

Velodog2 wrote:It appears Daconil fungicide also contains the active ingredient chlorothalonil mentioned above in Bravo fungicide. An unsavory chemical to be sure, but what else to do? The Wikipedia description of Leaf Curl Fungus as mentioned in Bretts link does not really seem to match my disease symptoms either, as there is no whitish bloom on the leaves at any point in the progression.

I don't think I added any link for Wiki. Leaf Curl Fungus is simply a name I have given it as I don't know what it actually is but I gave several similar fungus. There is a possibility it is a new fungus as well. I know a pathology test was done and it was identified as a fungus but the name of the fungus was never passed on.
I can only guess you have not registered to see the pictures as you would see what I had looks the same as the pictures shown here. The only thing that could make me more sure that we are dealing with the same thing is a pathology test.
The wetness would be an encouragement for the fungus. Depending on what value you put on the trees affected I would treat with chlorothalonil considering it is a nasty chemical. The long term plan at the moment for me is removing all garden debri from the entire garden over winter good treatment of lime sulfur and probably a dose of Bravo as they leaf out just to make sure they get a good start for this year at least.

Doing a search on Daconil it is made by the same company that makes the bravo. Although the active ingredient is exactly the same it is registered as a different resistant group and states different fungal use. Have no idea how much difference it makes. Might be worth calling the manufacturer to get some advice on what the difference actually is?
http://www.syngenta.com.au/Start.aspx?PageID=10101&ProductID=786125&menuId=
http://www.syngenta.com.au/Start.aspx?PageID=10101&ProductID=47752&menuId=2053

Jim there has been many suggestions such as yours put to people with this. It makes no sense as collections that have been trained in the same place for years with no trouble are now desiccated by this. I have trees growing in full sun that are fine. Also as stated one tree right next to another with this shows no ill affect.
As stated in the linked thread. Applications of the bravo that where recommended in the results of the pathology test showed undeniable results in correcting the issue. Whether it is a leaf fungus or systemic fungus I would say the later but I kinda thought they where all Systemic. Something I am sure to learn in the future. The bravo is meant to work by suppressing spores so not sure how that fits in with leaf or systemic fungus?

In my experience, there is no fungicide available to the general public that will reliably "cure" a tree with a fungal problem, whether roots, leaves, or otherwise. They're all much better as a preventative. I neither trust nor know much about systemics.

But I've e-mailed Dr. Nina . . .

JimLewis wrote:But I've e-mailed Dr. Nina . . .

Thanks Jim. I was kinda hoping she was watching this thread.

JimLewis wrote:In my experience, there is no fungicide available to the general public that will reliably "cure" a tree with a fungal problem, whether roots, leaves, or otherwise. They're all much better as a preventative. I neither trust nor know much about systemics.

But I've e-mailed Dr. Nina . . .

This fungucide like most others I know of is stated as a preventative measure.

GENERAL INSTRUCTIONS
BRAVO is a protectant fungicide only. BRAVO must be applied before diseases occur/become established to be
highly effective. Use disease warning services or past history to determine timing of first spray. If diseases are
already present, then an eradicant product should be used first and mixed with BRAVO.

I had already seen this work for someone else with the issue so I tried it anyway and you can see from my link that it worked very well some how? I can only guess that as a protectant it prevented the fungus spores from getting to the new growth as it emerged.
I would be intrested to know what an eradicant for fungucide is. An Aussie nurseryman swears by Phosphorous acid or Yates Anti Rot here. The best thing about it is that it is as harmless as a bottle of coke.

Hi guys! Dr. Nina here (for people who don't know me because I'm been so quiet lately, I'm a plant pathologist with the USDA studying tree diseases). I'm based in Maryland, and I can tell you that this heat is injurious to maples. However, the symptoms that the original poster photographed (nice photographs, incidentally) did not especially look like heat damage. Also, the wide range of plants affected did not sound like a fungus. It could be *several* fungi, and if we had been having wet weather, I could see it simply being a "fungus-y" summer; however, it's been very dry. So I'm thinking about abiotic factors. One of the later posters mentioned alternating neem oil and a sulfur spray, and it's a bad idea to alternate oils and sulfur- it can lead to phytotoxicity. It is also a bad idea to spray sulfur in weather over 80 F, and that's what we've been having for weeks now in Maryland. It's also a bad idea to spray certain oils in hot weather, and oils can be phytotoxic to delicate plants (such as maple) no matter what the temperature. The symptoms in the photo are consistent with chemical injury and completely inconsistent with Verticillium.

The trouble with hitting "reply" is that I can now no longer see the original poster's post, so I'm going to hit "send" and then check to see if oil sprays were being used. However, for everyone else out there: you should be very cautious about using ANY kind of spray in hot weather.

I just looked, and yes, the original poster is spraying neem oil. Now, not to be harsh and judgmental, but unless there's a reason to be spraying neem oil, original poster, why are you spraying neem oil? I'm a great believer in only using pesticides when there's a known pest and you know the pesticide will be effective.

Thank you for the advice Nina! However I assure you that I was not spraying anything until the symptoms were quite evident. The last picture posted is most like my acers, with the growth tips looking like a blow torch was put to them - totally blackened. I have now noticed something maybe similar, at least like the op's other photos, on other species, but I would hesitate to conclude it was the same thing. I am however starting to see definitely the same thing on some landscape palmatums now, although less severe. I have gotten hold of some Daconil and am using it judiciously (I hope). The trident is definitely growing through it ok for now, although this started before the Daconil treatment. Another round of growth is beginning on the palmatums and I'm hoping to be able to get them established with some leaves hardened off before and if it hits again (it seems to go in waves, allowing a period of growth and then bam, total dessication with the softer new growth being more quickly affected).

If you are interested in this much Nina I could probably show you a specimen - I'm sure you are not far from me.

Same here Nina. Symptoms where there for several years before I used anything on it. Last year was exceptionally bad which seems right being that it was reported as our worst year in 20 years for fungus due to heavy drought breaking rain.
I was also confused by the wide variety of species affected and although there was some variation of symptoms there was also a vast amount of similarities from species to species that it made me at least consider it was the same ailment.
As I stated someone else who had a trident affected the same way had it tested by someone such as yourself and it was positive for a fungus disease and the fungicide recommended definitely worked. This was evident by recovery shortly after use and return of the fungus when I stopped treatment as I was concerned with it's toxicity.

OK, how about maple anthracnose?

http://www.entomology.umn.edu/cues/dx/CB/m_anth.htm
http://www.extension.iastate.edu/Publications/PM1280.pdf

If it were rainier, I'd be suggesting this seriously. In this weather, however, I'm not sure. I had seen some dogwood anthracnose this spring, so I suppose it's possible that what you're seeing was initiated in the spring. If so, you don't need to spray now.

I am havin the same problem as well!

Anthracnose was my best guess as well Nina. I mentioned this on the Aussie forum and gave this link.
http://www.na.fs.fed.us/spfo/pubs/fidls/anthracnose_east/fidl-ae.htm
It is very disappointing that the name of the disease was not past on when the pathology test was done but this is my best guess as to the symptoms.
We really have had a bad year for fungus here as Winter sets in I see fungus on various trees and plants around the garden coming out as the leaves die off.
Also i now see fungus everywhere pointing it out to many people on street trees and in their collection.

I agree about the not bothering spraying if you Guys are late in the season. I stopped spraying at the end of the season and just waited for the Autumn cold to get rid of the leaves. Now I am doing my best to clean the whole garden. Spraying with lime sulfur. I am considering giving the important trees a dose of Bravo early spring as they leaf out just to make sure they get a good start.

Would you recommend any other action? I have several feature trees in the yard that have also showen signs of this so I fear I may never be able to control it?

Is it to late in the year, mid July, to defoliate the maples and then treat with Bravo as the new growth starts?

Ricky,

To me, your maple appear to be suffering salt burn. There are several different reasons for this condition to occur.

Paul

by Brett
Jim there has been many suggestions such as yours put to people with this. It makes no sense as collections that have been trained in the same place for years with no trouble are now desiccated by this.

As I said Paul you have given me this opinion on the Aussie website. Considering a pathology test found fungus, the treatment recommended worked and the fungus returned when treatment halted. Street trees surrounding my town where also affected. Collections that where not even fertilised where affected. Trees growing in full sun and extreme heat fared no different and some times better than those shaded. Well established collections that had always grown well where desiccated by this.
The affliction was wide spread over at least the state of NSW.

I can agree that having a toxic level of salt in the soil could worsen this affliction but I really doubt that is what is causing this.

Is there any reason you can say it is not a Fungus?

Rick I would not defoliate, I found that only weakened the tree and gave the ailment a leg up. In my layman words the tree seemed to rely on the continued energy created by the leaves to fight the fungus.
I am not sure spraying with Bravo this late in the season would be worth the risk of using such a nasty chemical either. I would recommend doing nothing fancy but manage their normal care with diligence. Without much top growth they may not use alot of water so be careful with watering habits.
I would say forget about having nice leaves this year. As long as they have a half decent amount of leaves (even severely damaged ones, any green left is making energy) left on the tree it will go dormant fairly content.
Plan on thourer winter hygiene and disease treatment as I stated above and look forward to a better year next year.

Maybe Nina has a different suggestion but that is mine

Dear Brett,

I was unaware that I had actually posted anything contrary to your opinion in this thread. In fact, I have specifically avoided commenting on this issue in a public manner due to the rabid responses it elicits from you; and my inability to convey any scientific concepts, or personal ideas to you. I fear your becoming increasingly paranoid about this fungus of yours.

If you look closely you will see my only response on this thread was to Ricky Keaton's maple photos. I think his maples are suffering from salt burn. I think this because I had similar leaf symptoms on a "Kashima" which was suffering from sodium toxicity.

Regards

Paul

Nothing Rabid Paul and nothing to fear just facing the facts of the issue!

so one reason for sodium toxicity could be from me foliage feeding or from me using softened water.
i am going to see my county extension office to see what they tell me about maybe this being a fungus among us!

Ricky,

I didn't say you had sodium toxicity, I said your leaves appear to be suffering salt burn. Yes, this can occur from overfeeding. I find japanese maples are very sensitive to salts. If you have access to an Ag extension officer take a water sample for an EC analysis, just because you can, he may be able to do a quick on the spot EC test. It will eliminate another unknown.

Brett,

"Nothing Rabid Paul and nothing to fear just facing the facts of the issue!"


I've thought about this for a while, and for the life of me, I do not know what you are saying.

Paul

Just wondering how everyone's trees were doing with this. Mine are hanging on but not pretty. The maples are decimated and raggedy, although the trident is better than the others, and I'm having problems with zelkova, apple, and pyracantha, maybe others as well.

I've gone through an entire spray bottle of Daconil and I cannot say for certain that it has had any effect.

Another symptom, related or not, is the new growth that comes out and manages to survive is now pale and yellowish.

I am beginning to consider the salt poisoning possibility. We have had almost zero rain here for the past 6-8 wks (we had some this past weekend, thankfully) along with record high temps, so the trees have been watered from the tap exclusively and profusely. If my water softener is a culprit, these are the perfect conditions for the problem to show itself. Also, I went back and checked my banking records and found that I added my water softener, after living with incredibly hard water for years, near the end of last July, about a month before seeing my first problems.

It wouldn't explain everything, such as why I seem to be seeing the problem in some landscape maples as well, but I am desperate at this point. So as annoying as it is, I am going to begin putting the softener into bypass mode and purging the line before I water with the hose now and see what happens.

Everyone needs to keep an eye on the calendar at this time of year.

The leaves of deciduous trees are getting old. Just like us old people, they start getting spots on their "skin". And the excessive heat we've had here in the Eastern USA hasn't helped slow the aging process either. (For us or them.) So many of your "problems" really aren't problems.

However, when spots or brown edges appear on a leaf that isn't automatically a sign of some dread disease. The first thing to do is to remove and destroy the affected leaf or leaves. By "destroy" I mean remove them from the area you bonsai grow in. The garbage can is fine. So is the burn pile if you live somewhere you can burn.

Then keep an eye on the new leaves. Avoid watering the leaves every day, if possible. (It is not possible for me because of my watering system, but I've had no leaf problems, either -- knock on wood.)

In the heat, full sun is probably not recommended for most broadleafed, deciduous trees. But bright shade, or full morning sun is probably OK.

Many leaf spots are caused by sucking insects -- the true bugs, mites, thrips, aphids, etc. Most of those are fairly easy to control.

In the summer, though, DO NOT USE any oils!!! If you do, you WILL have leaf problems. That includes Neem or dormant or light horticultural oils. The sun will hat the oil and cook the plant. In my personal opinion, Neem is dangerous to us and the environment; I would never use it. It is overkill for bonsai at any rate. A spray with a pyrenthrin in it (many houseplant sprays at Home Depot or nurseries are pyrethrin sprays) is sufficient to control any of them (and a spray of water into the foliage will take care of spider mites). Spray in the early evening for best results.

Some plants are prone to leaf spots and burned edges. We've already discussed Japanese maples. But the rose family -- apples, pears, hawthorns, plums, cherries, peaches, hackberry, cotoneaster, Potentilla, Mullberry, etc. -- almost all get spotty leaves at this time of year. Sweetgum is another. Elms are more susceptible to black spot in late summer and fall. There's no treatment that works at this time of year.

Just remove leaves and destroy.

But mostly, don't have a hissy when you spot a spot.

Generally good advice Jim, and may in fact be relevant to some of my trees. I won't belabor the point of how unusual the degradation is on the others as we've covered it already in depth. Been at this game for nearly 20 yrs now and I have a good idea of what's normal for late summer. Lordy.

Velodog,

How does your water softener work?

Paul