Japanese Maple Bark Related Issues

Discussion in 'Maples' started by mjh1676, Jul 31, 2005.

  1. mjh1676

    mjh1676 Active Member Maple Society 10 Years

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    There is no doubt that the condition you describe can occur and does occur. The Vertrees reference "Japanese Maples", all editions, describes a number of fungal infections, Fusarium being one that can attack branch tips and buds as well as the bark tissue at or near ground level. This type of external infection is typically a disease of seedlings or young grafts, and more so in the greenhouse setting. Buy, we can see this sort of dieback on branch tips, especially new growth, if we force it too late in the season and we leave soft nitrogen-rich growth to overwinter. This soft growth can also be attacked in summer if we have a situation with poor drainage and excess nitrogen, one that I have had to deal with and have described before. In this type of stituation, a correction of cultural contions is a must. Any blacked or dead wood should always be pruned at first opportunity to prevent spread. Sometimes removing a blackened young twig just above the next health bud pair can stop the infection that might have continued to travel down the twig. The pruning in combination with recognizing and correcting cultural conditions can clear up the problem for us without chemical treatment which is often uneffective.

    Many of us are buying smaller and smaller maples now in an effort to acquire new and more rare varieties. Young maples are very suseptible to various fungal and bacterial blights and we as end-growers of these very small plants are being faced with issues that only the primary growers used to be concerned with on a regular basis. While a 5gal or larger plant can easily recover from some twig dieback or a minor fungal attack, a young 1 or 2 year plant faces death when faced with the same attack.

    While I cannot be certain, here in my neck of the woods, I face a much greater challenge with systemic pathogens than I do with external fungal infections. I do get some mildew in the summer, but I have not lost a plant to that, to my knowledge. Some common treatments I use or have used are Lime-sulfer and dormant oil. I have used Phyton 27 (soluable copper sulfate) both alone and in combination with a Bayer disease control product containing the antifungal tebuconazole. I have mixed the tebuconazole with the Phyton in the same sprayer on occassion. Copper sulfate is advocated by some as a soil drench near bud break to help erradicate some soilborne pathogens. All except the sulfer and oil can be applied during the growing season, but I have applied sulfer to some supposed pseudomonal lesions on the lower trunk area of a maple or two with success. I would consider these applications accessable to the home gardener--there are many many more products.

    I can hear the backlash against blind application of chemicals, so I must say that it is best to have some idea of what you are treating and just treat the infected plants. I don't always work that way, but I am not that refined yet. While there is a good deal of preventative spraying that goes on with many sorts of plants, we should not have to do that for maples. A healthy plant in good culture should not need preventative spraying of any type and I cannot advocate that. For containerized plants may benefit from the spring soil drench as a bit of insurance.

    Anyway, we can handle the rest of this discussion on a case by case basis as I have gone on long enough.
     
  2. schusch

    schusch Active Member Maple Society 10 Years

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    Thanks, MJH - for the additional elaboration. Good advice not to let blackening of twigs, for instance, spread, and prune immediately. I'll take a picture of the branch I was mentioning, and post it, for your and other people's consideration (it might take a few days, though). There are a number of 'lesions' or 'irregularities' on maples, and it'd be good to know which ones are of concern, and which ones aren't - and what possible treatments are. Photos could help with that.
     
  3. schusch

    schusch Active Member Maple Society 10 Years

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    Here is a picture of the branch (on an osakazuki in a container) I was talking about. It started with splits in the wood, with a reddening or browning of the branch. The leaves are however fine on this branch (and on the whole tree - no dieback, no leaf burn, nothing). This started months ago, and has slowly spread down the branch. As cause I suspect the soil not draining sufficiently because the particles are too fine. I will change the soil in a couple of weeks.
    Any thoughts? Should I cut the branch immediately? Use any fongicide?
    Thanks for any input.
     

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  4. mjh1676

    mjh1676 Active Member Maple Society 10 Years

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    Thanks for the photo, it is very helpful. No, tight bark is not the problem there. I would suggest you go forward with looking at the root system and remove those infected branches right quick-like.

    I don't have much time at the moment, but later tonight or tomorrw, I'll reply further. If you have some lesions elsewhere on the plant that are small, where whole branches are not involved, you might be able to save them. Anything that looks like what you photographed needs to go.

    How long has the condtion existed and how did it start? Where on the plant? Do you have any larger cracks or splits? Done any heavy fertilization, or when was the last time you fertilized?

    I'll get back to you.
     
  5. schusch

    schusch Active Member Maple Society 10 Years

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    Hi, mjh- thanks for taking a look. The condition started on that branch, somewhere in the upper half about 6-9 months ago. There is another branch where it has started. The plant is otherwise healthy: the leaves are not affected and the tree is growing. The splits or cracks are thin, and present only on this branch and a little on another. I'll repot with a better draining mix and look at the roots in a couple of weeks or so. Fertilization was done with osmocote, not excessively: no leaf burn, at least. (We discussed the issue of fertilization in the other thread: I am now leaning towards granular - possibly organic - after leaf break). I think it's a fungus - not necessarily the cause but it's present - btw, and intend to use a chemical or two. I have access to python 27, as well as a couple of other products that were recommended to me.
    I talked to a grower here, and he said they use twice a year applications (on branches and soil, if I understand correctly) of fongicides as routine, preventively - in the fall, and just as the leaves come out in the spring - on all young maples, to prevent these types of developments.
    Thanks again.
     
  6. mjh1676

    mjh1676 Active Member Maple Society 10 Years

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    I wanted to give you a few more photos to look at. The 1st one is what I believe to be a pseudomonal lesion low on the trunk of an Acer caudatum. I had this tree in the landscape for a year and when we moved I dug it up. What I found is that it had been sitting too close to our lawn in a puddle of water. After digging it, I put it in a 15gal pot and brought it to our new home. When the summer heat hit, this lesion appeared as well as the condition in the second and third photos.

    I have since pruned the infected branch in the photos and planted the maple in a drier location in a friends yard. I will be inspecting the lesion this spring and deciding on what treatment it might need. I would expect it to develop into a crack if I do nothing. The branch in the second and third photos has been lost to verticillium.

    Now, I am giving you my suppostion about these conditions, as we can never know what truly has hit us without a laboratory test, but these two conditions seem to be pretty distinctive in maples. There is no treatment for the verticillium that will be effective except to try and give the plant the most ideal conditions possilble. We have other options in our fertilizer regimens, but we are then working to mask the infection or help the plant control it.

    As for your branch, I am struggling a bit, but I want to say that it is verticillium you are dealing with and there may possibly be some signs of tight bark. You said the tree is growing well. What happens to the leaves on the branches that are effected? Verticillium will usually cause the leaves to dry and dessicate as it is a vascular disease. The Aka shigitatsu sawa I posted a photo of before is an example of how things could look. Can we see a photo of your whole tree? What is confusing me is the black mottling under the bark. In verticillium, we first get the orange color on the twig and then as death progresses, the black coloration sets in.

    MJH
     

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  7. schusch

    schusch Active Member Maple Society 10 Years

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    The leaves on the affected branch were fine throughout the season. The buds right now look fine, too. It started with little splits in one area, the discolouring came later. It then progressed.
    My question when I see your photos, and the others is does the colouring (reddish, darker brown, blackening) indicate a particular disease or fungus, or is this a typical reaction in maples that indicate a wider variety of possible infections and causes. (Thus, for instance, I've seen the darkening on small twigs that I cut off, and that was the end of that.) I guess it's necessary to get tests on affected branches. (If I do cut the branch I'll have it tested.)

    Any thoughts on using fongicides routinely, as a preventive measure? Also: since I do have a bottle of python27 do you have any thoughts about its use, any recommendations?

    I'll try to get a pic of the whole tree, but it will take a few days.
    Schusch
     
  8. LJY

    LJY Member

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    Hello,

    I've been doing a little bit of research on verticillium wilt. As it is a soil fungus, can a container maple be "cured" by bare-rooting and fungicide application? Has anyone tried this successfully?

    Thanks for your input,
    LJY
     
  9. mjh1676

    mjh1676 Active Member Maple Society 10 Years

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    The soil can be treated and theorhetically cured, but this is most applicable to a potted situation like what you are referring to. Growers will treat plants with a copper sulfate soil drench usually in the late winter or spring to control or prevent VW. I don't know how frequently it is practiced, but I have seen it recommended and have done it myself. This type of soil drench can also help in controlling other soil-borne pathogens, but it can be time consuming and expensive.

    Once a plant is infected the application of systemic fungicides like soluable copper sulfate rarely works or shows much benefit. Removal of infected wood and maintenance of vigor and proper culture are still the best treatments for infected plants.

    When it comes to maples, it is more common that we receive the plants with infected understock or scion wood and it is less common that we introduce it through our potted soils. Buying clean maples and seeing parent stock plants is still the best way to enusre longevity. When planting maples in the ground attention to culture and proper drainage will protect the maple from diseases like VW.
     
  10. schusch

    schusch Active Member Maple Society 10 Years

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    Hello, everybody, and MJH-

    Some time ago I submitted a picture of a branch on my Osakazuki that presented signs of disease. I talked to the grower who had sold it to me, and he said it was most likely fusarium, and that I didn't need to cut the branch, but needed to use a fungicide - which I did. I hesitated cutting the branch, even though most people here advised it - I finally decided to wait and see. Here are two pics - one of the branch, the other of the whole tree. The tree seems healthy, and grows, the leaves on the infected branch are fine, too.
    Any thoughts?
     

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  11. mr.shep

    mr.shep Well-Known Member 10 Years

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    The tree seems healthy, and grows, the leaves on the infected
    branch are fine, too.


    Fine for now although that can be disputed by the elongation
    you have in the branch and no new growth to come from the
    infected area. For us here in a warmer climate, wait for the
    tree to stress and watch what happens to the entire branch.
    People in cooler climates as well as in warm and humid areas
    can have their Maples live with this disease but when the Maple
    is overcome with it is when you will wish that you had pruned
    off the branch. You can gamble and roll the dice and win for
    a few years but we cannot risk doing that here. What you need
    for this is a systemic fungicide and hope that no other "new"
    areas of it show themselves anytime soon elsewhere in the tree.

    MJH was right that this is not Tight Bark.

    Sometime just for the heck of it look up how Fusarium affects
    Corn and Tomatoes and then look at how Fusarium and Dothiorella
    affects Palm trees and see if topical sprayed fungicides are in any
    way effective for control of the Pycnidia or fruiting bodies once
    you see them. If people even suspect they have Fusarium wilt on
    their Maple do not leave the branch in tact and please do disinfect
    your pruning shears after each and every cut you make.

    Jim
     
  12. schusch

    schusch Active Member Maple Society 10 Years

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    Hi mr shep/Jim -

    Thanks for your input. I have used a systemic fungicide, and will see how it develops. I am not wedded to that branch, so will cut it, especially if it stagnates. I thought it'd be worth waiting to find out more about the disease and how it affects leaves, etc, especially if it shows in another of my maples. But, as I said, if cutting off the branch is the way to do it, no problem.
    I do disinfect my shears, but it's a good warning. I assume the grower suspected it was fusarium since he has encountered it over the years amongst his trees, so I wonder whether such disease spreads through oversight: not disinfecting tools, having different employees work on trees over the years, etc.
    Again: thanks for your reply.
    Schusch
     
  13. mr.shep

    mr.shep Well-Known Member 10 Years

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    When we see a lesion on a branch we are not sure of
    it is wise, prudent here with our warm and dry climate,
    to just go ahead and remove it. Better safe than sorry
    as we've seen what can happen when we've gambled and
    lost. Not all Maple growing areas will have the same
    fears as we do here as we do have one limitation that
    some other areas do not have to be as concerned about
    and that is we do have Verticillium in many of our native
    soils.

    Even the mention of Fusarium wilt to a Southeastern
    Cotton grower and Verticillium wilt to a San Joaquin
    Valley Cotton grower used to send shivers through
    people, before crop rotation techniques and fungicide
    coated seed came about, as they learned just how lethal
    these two pathogens can be. Fusarium wilt/nematode
    complex can still be a major growing concern in the
    South.

    I am not sure I have seen Fusarium wilt in a Maple but
    that is not to say that it cannot happen. I believe Mr.
    Vertrees was referencing another pathogen when he
    mentions Fusarium in his books. We should see our
    evidence of Fusarium in the leaves first as an unusual
    mottling of a darker green color with a noticeable brown
    discolored area on the backside of the leaf right above
    where the leaf attaches to the petiole. We will more
    likely see Fusarium affect established seedlings and
    older plants and even when the seeds are germinating
    as the seedling epicotyl is emerging up through the
    soil we will more likely suspect Pythium or perhaps
    even Rhizoctonia, if it is known to exist in our soil,
    as being the damping off causal agent as opposed to
    a bona fide wilt that generally waits for a few sets of
    leaves to develop first but usually hits the plant later
    rather than sooner like Pythium does.

    Jim
     
  14. schusch

    schusch Active Member Maple Society 10 Years

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    Mr shep -

    thanks for the additional info.

    I looked for the tell tale signs you mention on the leaves, but couldn't find any yet. This may still come later.

    I feel I need to keep a close eye on that particular tree, and find out as much as possible about the pathogen, since this may show in other maples. I did use the fungicite the grower recommended, as well as a copper based one a bit earlier. The grower also advised me to use a preventive fungicite fall and spring on all of my maples for another 5 years - any ideas on preventive spraying?

    We discussed reasons for disease in maples earlier and in another thread. In relation to that I noticed that some stores selling maples in France, for instance, advise spraying preventively - some of the other advice they give (like use peat, and on the amount of fertilizer) was not that convincing - some their recommendations might weaken the tree in the first place - so I couldn't help wondering about the preventive spraying as well. I think my tree might have been susceptible because of the soil mix I used last year (too dense, not enough drainage) - so obviously it's not a good idea to spray when the causes have not been addressed.

    Anyways, thanks again for taking time to share your knowledge.
    schusch
     
  15. mr.shep

    mr.shep Well-Known Member 10 Years

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    Fungicide spraying of Maples is where we will have a
    conflict to some degree. I've never used a fungicide
    on my Maples as I did not really need to. We do not
    see Powdery mildew on our Maples here unlike some
    central and northern coastal areas of California and
    pretty much throughout much to all of Oregon. I've
    even seen Downey mildew on Maples in areas in
    Oregon. If our propagation techniques are clean we
    do not see signs of the wet lesion form of Pseudonomas
    in our Maples here either. Where we run into trouble
    is getting plants from Oregon and elsewhere and using
    those plants scion wood for grafting or Summer budding
    in areas that will bud their Maples.

    Soil drenches for root rotting organisms such as
    Phytophthora are really not needed here either and
    neither is lacing our seed for germination with a
    fungicide such as Captan. When we got hit with the
    blast form of Phytophthora which caused real havoc
    with some of our dwarf form Maples here back in
    1989-1990 (have not seen it here since I might add).
    I am not so sure if a systemic fungicide application
    or a topical applied spray would have helped much
    as many times it is not the spray we use that is relevant
    it is when we apply it that I feel is much more important.
    If we do not know when the tree became infected it is
    hard to know when we should have tried to prevent it
    from happening and even then the thought went through
    our minds that it may not have made any difference.

    There are areas that probably should use a fungicide
    spray as a preventative much like us using a spray to
    suppress and prevent Peach Leaf Curl on our Peaches
    and Nectarines or a spray to prevent Hull and Brown
    rot in our Stone Fruits.

    What I would not do as I've seen it done is that we have
    to be very careful using an oil spray on our Maples as
    I've seen the effects on the young twigs and juvenile
    branches when applied at the wrong time of the year.
    We can cause harm if we use a lime sulfur spray when
    the weather is too cool and also when the weather is
    too warm. So, for us to us an oil spray we have a small
    window of opportunity or we risk causing harm to the
    plant.

    I think copper based systemics are probably the best for
    most Maples as a preventative for a disease that we know
    in advance that our Maples may or will come in contact
    with. If our main concern is with a soil borne Verticillium
    and we want to transplant 10,000 seedlings into the ground
    then we may want to use a soil drench about 4-6 weeks
    prior to planting in some areas but of course not all areas
    will need or require the drench just to be on the safe side.
    Once the plants get up to about a foot tall we may then want
    to come in with a systemic but here we would not do it and
    I never have needed to but in areas of the Pacific Northwest
    it may be advisable as some locations do have some problems
    with root rotting organisms, even Pseudonomas and have some
    Verticillium in some of their soils.

    Really, there is no need to start applying a fungicide on your
    Maples unless you feel you have to do it. One infected Maple
    is not going to infect the rest of them, even when we are dealing
    with Powdery mildew as we are facing much of the time a rather
    selective disease that will hit some varieties of Maples and will
    leave others pretty much alone. Why spray them all if that is the
    case? If we can pinpoint which Maples such as Ukigumo is in
    Oregon that are more likely to be susceptible to Powdery mildew
    then we may only need to spray those Maples and not all of them
    for that disease.

    Personally, I'd rather have my Maples come in contact with a
    disease and develop some resistance to it. I can get away with
    that approach here but some areas are better off just to go ahead
    and treat their plants when they already know if they do not use
    a spray or a systemic they will get hurt. Sometimes, the decision
    is already made for us and there is no sense fighting it just go
    ahead and use a fungicide spray as a preventative rather than risk
    the effects we will see on our plants later if we did not do it. If
    Maples or plants in your area are more likely to be attacked by a
    disease then you may not have any other choice but to try to ward
    off the effects of the disease as best as you can. I can name a lot
    of plants that if people had used a comprehensive preventative
    spray program that many of those plants would still be alive today.
    The people that seem to object the most are the ones that are not
    affected by our decision to spray or not to spray at all. You do
    what you think is best for your growing operation and if it means
    using a systemic, soil drench or a copper based fungicide spray
    then go ahead and do it. It is the one time when we listen to people
    that are not affected by our decision and hold off from applying a
    spray we knew we should do is when we get hurt the most. Not
    only with the visible signs we see from the plants but also that
    we went against our own better judgement and it is the latter that
    we will think about over and over every time we look at the plants
    that took a beating because of us not doing what we knew we should
    have done.

    Jim
     
  16. schusch

    schusch Active Member Maple Society 10 Years

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    Thanks mr shep/jim-

    this is very valuable advice, particularly on copper, sulfur and oil based products. (I had bought an oil based liquid against scales, but was warned against it by Layne - just in time.)

    I think I could also cut an infected twig, or branch and have it analysed by a lab.

    As regards helping the trees develop a resistance - already changing the soil mix to a more optimal mix should help.

    Finally, I have different maples from different growers, some from Esveld who, I was told, hope to lessen the need for spraying with their different approach: I'll not preventively spray those, and compare the results in the coming years.

    Thanks again.
     
  17. graftedmaplecollector

    graftedmaplecollector Active Member 10 Years

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    The thread in question. Should be stickied no doubt.
     
  18. Daniel Mosquin

    Daniel Mosquin Esteemed Contributor UBC Botanical Garden Forums Administrator Forums Moderator 10 Years

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    Stickied again.

    No malice was meant by making it unsticky, since some have implied that. I merely wanted to not have a front page full of stickied threads when people first visited the maple forum.
     
  19. Gomero

    Gomero Well-Known Member Maple Society 10 Years

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    I question that this thread be stickied.

    It started correctly raising the issue of bark related problems with well known and documented situations
    . Then Mr. Shep came up with a term 'tight bark' used privately by him and a few other people to encompass what?. I've tried to understand.
    In the first paragraph he first talks of 'disease'. In the second of a 'pathogen' (i.e.: a micro-organism or virus that can cause disease). In other threads, I've read that is neither a disease nor a pathogen; then what it is?.

    Further down in his thread he makes a scientific claim
    without giving any evidence or references.

    To me it is hardly believable that an apparently widespead 'disease' that
    is 'discovered' /'unveiled' today when maples have been grown by centuries all over the world.

    An in-deph literature search of the term 'tight bark' shows that, in arboriculture this terms means:
    This I understand.

    Having shown the pictures supposedly with 'tight bark' to people with long experience growing maples, they tell me it could be well-known problems, described in the refernce books. Sunburn/sunscald seem prevalent since many of the branches affected by 'tight bark' are exposed to the sun.

    I am not saying that a bark problem called 'tight bark' does not exist. I respect others opinion and their right to say whatever they want in the forum but, taking into account everything I've seen and read, personally I do not believe it.

    Considering the flimsy scientific evidence given, I believe that a forum managed by a University should not endorse those claims by sticking the thread. A disclaimer seems more appropriate here.

    Gomero
     
  20. Daniel Mosquin

    Daniel Mosquin Esteemed Contributor UBC Botanical Garden Forums Administrator Forums Moderator 10 Years

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    Writing as a representative of the University, I'm comfortable with highlighting something like this to scrutiny and skepticism. This is, in fact, a strength of forums - anyone can join the discussion and challenge convention or expound a new idea.

    To be sure, some censorship occurs, particularly when an advocated idea has been proven false. When something has been proven true, we can point to it as an ideal. When something has not been proven, though, is when things can get really interesting.

    Gomero, a post like yours is extremely valuable in ensuring that everything passes muster. I'm sure the advocates of this idea appreciate your skepticism, as it will give them a chance to bolster their arguments or refine their presentation of evidence.
     
  21. mjh1676

    mjh1676 Active Member Maple Society 10 Years

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    Daniel,
    I appreciate your point of view with regards to Tight Bark in that it warrants a further look to be proved or disproved to the satisfaction of those in the scientific community and likely many people that grow maples all over the world. Clearly I have chosen to belive that it exists as described, that it is as serious as it sounds, and it does effect countless numbers of maple trees all over the world.

    It is not important to me that I have the piece of paper in my hand that shows lab results or scientific data and that is certainly what separates me, and many of us, from the educated scientic plant community. If feel my education in the pharmaceutical sciences was presented with a broad enough scope that I can surmise how this disease might funtion and exist and it seems reasonable as no one else has posed a better answer.

    Gomero,

    Quite a response.

    I think you must be careful when you assume the University endorses anything in this forum beside the Botany Photo of the Day. I certainly mean no disrespect, but nrealy 100% of the contributions of this forum have come from outside the University and certainly the Universtiy does not use the Maple Forum (at least) as a vehicle to present any of its research or findings. They do not directly contribute or direct the discussion with relation to any research on maples that I have seen. So, "sticking" the tread is a service to the forum as it was created to deal with a number of diseases visible in the bark of maples, Tight Bark being only one of them. Of course they do not endorse it. They rarely even moderate the forum.

    If it is that big of an issue to you, Daniel can post a Poll and we can vote--no big deal to me.

    I know you have discussed Tight Bark with others, including people that grow maples, and you have come back with the standard answer that we always hear--sunburn and sunscald are the most common. That is fine. What bothers me most is that they cannot tell you what the cause is. If I bring them a leaf or a twig that is dessicated or blackend or burned, can they tell me what did it. Or do I get to hear it was a bacterial or a fungal problem or I didn't water correctly or the ever-popular fertilizer burn.

    There has to be defined and specific answers for what happens to maples and what it looks like. If we have a psuedomonal infection of the lower bark then it looks like one thing. If we have a phytopthora attack it looks like another as dose mildew. Anthracnose and verticillium have to have a given appearance and presentation. These diseases, like in fruit trees and in other species, occur under certain conditions and in certain seasons. For someone that knows the plant and has grow them for a long time and studied how they grow and behave--that person or people should rightfully know the answers to these questions. The answer: "oh, it could be sunburn" just doesn't cut it with me. It gives them no credibility with me when it comes to diseases. Yes they might know how to grow and propagate the plant, but that answer is a scapegoat answer. How many maples really suffer from sunburn and sunscald, to an extensive degree all over the tree? Why is the trunk of the maple in "Did my maple catch Verticillium" riddled with scarring all along the trunk--this is certainly not the most sun-struck area.

    Why does what we are calling TB usually move up through the tree in many cases? It usually starts in the bottom 1/3 of the tree and moves upward. Yes we eventually see the most dramatic signs in most sun-struck areas, but we can always turn to the trunk to see a lot more.

    I feel the issue of TB is an important one and I can see how the lesions effect my plants. Knowing about it and possibly how to control it will allow me to be more successful with my maples and will allow me to choose more wisely when I buy them. I think others feel this way and I am happy that they are willing to look into it further in their own collections. I think it is a hard concept to grasp and as we grow the plants over time we will learn how to best control the problems that effect them. I think at the least, it would be my obligation to share my opions about tight bark and other diseases if it will prevent people from buying and planting what I feel are diseased and problematic maples. Surely, Tight Bark or sun scald, you would not recommone someone buy a tree as Shelli did with a trunk covered in callous.

    By the way, did anyone ever help you to determine if your Akane had anthracnose? Would be interested to know what your friends have said after seeing the photos.

    Anyway, here are a few more photos of the unproven phenomenon of Tight Bark. Let me know if you have another explanation for these lesions in mostly shaded areas of the plants.
     

    Attached Files:

    Last edited: Jul 26, 2006
  22. graftedmaplecollector

    graftedmaplecollector Active Member 10 Years

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    It is obvious that TB is something even if you don't agree that it is a disease.
    The fact that it is an issue is more of a reason to have it stickied than anything.
    Theories are meant to be discussed, proven, or disproven no real institute of learning would censor a serious topic of scientific discussion like this.
    Besides, unless you attend, teach, or admin at said university you have no right to
    critcize their policy whatever it might be.
     
  23. mr.shep

    mr.shep Well-Known Member 10 Years

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    I did not name this disease or the symptoms of it, Tight
    Bark, a consortium of people in Japan and in the US
    called it by this name. Several plants that came in from
    Japan upon being in the US as early as the teens started
    showing signs of a disease that affected the bark externally.
    The symptoms of the disease appeared to be much different
    than what people initially felt was Verticillium in the plant.
    By the way it was the Japanese that first felt that there was
    an internal Verticillium that was later proven by the University
    of California and other Universities. A second internal form
    was later suggested and it was also proved to be in the plant.
    I am not referencing the quick decline form in either case
    as most everyone at one time knew which soil borne fungus
    it was. Now we have Universities that got wind of
    Verticillium in Maples from other sources and have made
    their own conclusions without actual testing of the Maples
    they are proclaiming that can be adversely affected by
    Verticillium. As much as it bothered me later that someone
    could make a boast in this forum that they could write a
    book on Verticillium with no formal training, I laughed
    at that prospect and then realized that based on what other
    Universities have written on Verticillium that affect
    Japanese Maples that he probably knew more than some
    of our researchers do as he claims to have had some hands
    on knowledge dealing with it, when so many people do not.
    Am I being facetious, perhaps not.

    Even one of my alma maters shows a photo of what
    Verticillium dahliae looks like on a plant but that is
    not how quick decline affects the plant. The online
    photo is a good representative example of V. alboatrum
    however. Some pathologists spell it V. albo-atrum.

    It was my dime that paid for the testing of Tight Bark
    and I am not willing to share what I know to people
    that have yet to show they can bring anything to the
    table.

    In 1988 I was asked to write a book on palmatum
    type Maples by five people that later grew to nine
    and I declined but I did agree to compile the
    information for them as a nameless ghost writer,
    to which I had various photos of leading collections
    in the US and Japan, even photos from Mr. Vertrees,
    sent to me to use in the book. In 1990 I hand presented
    the manuscript to a University in Japan as it was in
    agreement that since the majority of the Maples
    originated from Japan from Japanese sources that
    it was more than appropriate for Japan to have the
    information. None of you can see it without my
    permission and the manuscript is not allowed to
    leave the building where it resides. The findings
    on Tight Bark from the University level are in that
    manuscript.

    By the way there are clear signs of Pseudomonas on
    Maples in this thread.

    Jim
     
    Last edited: Jul 27, 2006
  24. Daniel Mosquin

    Daniel Mosquin Esteemed Contributor UBC Botanical Garden Forums Administrator Forums Moderator 10 Years

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    I'd hate to think a university or its representatives could only be criticized internally.

    I'm comfortable with what Gomero said, and I'm certain he is willing (as am I) to respectfully disagree on what approach to take.
     
  25. Daniel Mosquin

    Daniel Mosquin Esteemed Contributor UBC Botanical Garden Forums Administrator Forums Moderator 10 Years

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    The language of conflict is anathema and unwelcome on the UBC Forums.

    I don't want to see battles. I don't want to see wars. I want to talk about plants with other people who want to talk about plants.

    For those (and there are more than one that I've noted) who have difficulty in acting in a way that is respectful, courteous and charitable to others, I have one suggestion: move on.

    There are plenty of sites that discuss plants and gardening. Perhaps your language and actions will be more welcome elsewhere.
     

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