JM with some curled leaves on different twigs

Discussion in 'Maples' started by Rosy_S_Cenario, Jun 21, 2017.

  1. Rosy_S_Cenario

    Rosy_S_Cenario Active Member

    Messages:
    33
    Likes Received:
    2
    Location:
    Berlin, Germany
    Dear maple lovers,

    with some good support from you last year Damage from overwatering, wind, verticillium - or all three? my potted JMs survived a sometimes harsh winter (-15°C and strong winds) well on our balcony.

    This spring they already did better than last year (I bought them early April 2016, each at ~10 years of age), so I was slapping my back having made no too big mistakes - but now all three of them (in individual pots, over a meter apart from each other) have a few curled leaves, maybe 10 on each plant, mostly on different twigs. All three plants developed them in the same week a week ago, while I was away. Please see the attached photos, if you can spare some time.

    Is this Verticillium wilt? If so, how can this disease develop in three separate potted plants? Any other suggestions as to what this symptom indicates?

    Thanks very much in advance!
     

    Attached Files:

  2. 0soyoung

    0soyoung Rising Contributor

    Messages:
    283
    Likes Received:
    364
    Location:
    Anacortes, WA
    Verticillium is inactive at temperatures above 70F/23C, and its effects tend to only be seen in early spring or late fall. So, it is unlikely that this is the cause.

    Verticilliium gets into the wood and clogs the xylem lumens, stopping the flow of water upward. Hence, the pattern is drooping, then curling and browning leaves going upward to the tip of a branch. There almost certainly must be bark damage at the point of entry. In other words, were this the cause, you also should be able to find damaged bark or a pruning wound just below the first curled brown leaves.

    Frankly, none of this is clearly the case in any of your pics. I can only guess that some twigs got broken (pic 1 & 3). Pic 2 shows drying at the leaf margins, something I am accustomed to seeing with a bit too much sun/wind or possibly water standing on the leaves - not to worry unless it spreads; if not sun/wind, spray every few days with 2 tablespoons of 3% hydrogen peroxide in a quart of water to stop the spread.
     
    Last edited: Jun 21, 2017
  3. Rosy_S_Cenario

    Rosy_S_Cenario Active Member

    Messages:
    33
    Likes Received:
    2
    Location:
    Berlin, Germany
    Thanks for your quick reply!

    Well, that makes me a bit less anxious... I also wondered why those curled leaves appear not all on one twig or branch per plant, but one here, two there... I examined all twigs with a curled leaf and only found visible breakage in two of them; maybe because some twigs are so short and small I could not see the damage, also being a novice to these plants.
     
  4. JT1

    JT1 Contributor 10 Years

    Messages:
    1,395
    Likes Received:
    425
    Location:
    Euclid, OH USA
    Leaf hoppers sometimes will cause the leaf to fail when they feed on the leaf stalk. Their bite releases a toxin that causes failure. Sometimes it's evident when the leaf and stalk are failing down stream from the bite and the remaining attached part of the stalk still looks good before completely failing.

    Leaf hoppers are hard to find as they are very small, fast moving, and try to be evasive. If you bump the tree or spray with a hose you will see them spring out in an infestation. It's possible that one found your maples as a quick food source and moved on. If they laid eggs it is hard to tell because they lay under the bark of last year's growth, but typically don't invade the older bark of the trunk.

    Late Spring and Summer watering.
    Leaf damage and spots, along with brown leaf tips start to show up on maples when watered with treated city water. Also never water with soft water treated with salt. Consider using rain water or filtered water instead. Also, get in the habit of only watering the soil and not the canopy. As heat and humidity build and nights tend to warm and air becomes more stagnant it creates an environment for foliage diseases to populate especially in the inner canopy. Avoid overhead watering and watering in the evening. At times you may need to water in the evening, just try not to make it a habit and avoid watering the foliage anytime you water.

    With the Mikawa Yatsubusa in the first photo, does the bark on the branch with the failed leaves have darkening? (Top left area in the photo) There maybe some darkening on a branch below too...I can't tell for sure from the photo...It could just be the lighting...
     
    Last edited: Jun 22, 2017
  5. Rosy_S_Cenario

    Rosy_S_Cenario Active Member

    Messages:
    33
    Likes Received:
    2
    Location:
    Berlin, Germany
    Thanks!

    We have good water here and I always water at the bottom, manually; we have a large 2nd floor balcony and no hose available. The plants are watered in the morning, before leaving for work. I crawled around each plant with much patience, but no insects and the like anywhere to be found. The darkening is just because of the lighting, from what I can tell...
     
  6. maplesandpaws

    maplesandpaws Active Member

    Messages:
    750
    Likes Received:
    17
    Location:
    KS -> northern AL, USA
    A possible cause for the drying/curling leaves might be that moisture isn't fully penetrating the rootball all the way to the center. I know you just potted them last year, so they should be good, but sometimes the roots grow very fast, the rootball was compacted in the center when you potted them, etc. Something similar happened to me last summer, one of my trees started getting a number of dried, curling/crispy leaves, all in the interior of the canopy, but nothing on the exterior. Normally, you don't pull a tree from it's pot and/or re-pot it in the dead of summer due to the stress this can put the plant through when it's already under stress from higher temps, but I felt it was either do this or risk the tree continue to fail past the point of recovery. I'm glad I did because, even though I'd only put it in that pot a little over a year previous, it had already filled the pot and it was bone dry in the center, despite having rain the previous day. So, I completely loosened the rootball, all the way to the center, put it in new soil in a larger pot, and kept it well watered and shaded for a couple of weeks (temps were in the mid 30s celsius), and it bounced back wonderfully. Not saying this is the case with some/all of yours, but it is a possibility.
     
  7. Rosy_S_Cenario

    Rosy_S_Cenario Active Member

    Messages:
    33
    Likes Received:
    2
    Location:
    Berlin, Germany
    Cheers!

    Repotting after only one year... I don't mind the effort, but the soil was prepared well. Plants don't like stress... Here, on the Berlin balcony, we have often strong winds and summer temperatures around 35°C, hence my last year's post, a few months after I received the ~10 year old plants. Last years, shortly after arrival, I had these brown tips in summer, but the plants were not quite accustomed to their new habitat. So far, they look better than last year - but those occasional shrivelled curled leaves alerted me...
     
  8. JT1

    JT1 Contributor 10 Years

    Messages:
    1,395
    Likes Received:
    425
    Location:
    Euclid, OH USA
    What is your source of information on Verticillium wilt?

    I have never seen information supporting such overall limitations as you describe and specific limits of "inactive at temperatures above 70F" or that "There almost certainly must be bark damage at the point of entry."
     
    Last edited: Jul 13, 2017
  9. AlainK

    AlainK Renowned Contributor Forums Moderator Maple Society 10 Years

    Messages:
    3,621
    Likes Received:
    5,192
    Location:
    nr Orléans, France (E.U.)
    Maybe the reference to early spring/late fall is a general observation about different types of fungal infection, especially the time when more trees can be infected if there's a source nearby.

    I had a look at "J. Maples" by Vertrees & Gregory, and did a quick search on the web but didn't find mention of temperature. But yes, fungus (mushrooms) develop faster in cool or mild humid environments.

    Yet, I had the confirmation that "Verticilium dahliae and V. longisporum are able to survive as microsclerotia in soil for up to 15 years"!!!

    Quelle saloperie ! (excuse my French).

    PS: I remember a thread on diseases or verticillium with lots of info on it including photos of sections of branches showing the dark coloration of the xylem: try this forum search engine.
     
  10. JT1

    JT1 Contributor 10 Years

    Messages:
    1,395
    Likes Received:
    425
    Location:
    Euclid, OH USA
    The time of year references, bark damage reference, and temperature reference makes me think they were referring to bacterium pseudomonas syringae. Of course we both know it can outbreak anytime during the growing season when the tree suffers stress. But conditions are optimum in early spring and late fall.

    Its my understanding that Verticillium wilt is favored by moist soils and a temperature range of 21-27° C (70-81° F) per APS.

    That is why I was interested in the source of information from @0soyoung that brought them to the conclusion it must not be Verticillium wilt because it's over 70F and "There almost certainly must be bark damage at the point of entry. In other words, were this the cause, you also should be able to find damaged bark or a pruning wound just below the first curled brown leaves. " (I don't understand how this makes sense based on the disease cycle of V. wilt)

    To be clear I'm not promoting that the tree has V. wilt, I'm asking where the information came from to support his criteria for ruling it out, because the criteria is something I never heard before.
     
    Last edited: Jul 13, 2017
  11. 0soyoung

    0soyoung Rising Contributor

    Messages:
    283
    Likes Received:
    364
    Location:
    Anacortes, WA
    In ‘Verticillium Wilt of Maple, Catalpa, and Elm’, Wysong and Harrell state that the optimum temperature for growth of the fungus [Verticillium] in plants is 65F to 72F. Growth rate curves are illustrated nicely in Figure 12 on pp 33 of Fabio Carapinha’s Masters Thesis. The ,growth rate of Verticillium declines very rapidly with temperature increasing above 72F, coming to a complete halt by about 85F, Hysong and Harrell note that microscleratia are produced in this temperature range.

    Wysong and Harrell also note that infection is most commonly occurs through wounds near or under the ground, though it can occur through undamaged growing root tips/hairs. I exaggerated for emphasis by saying 'almost certainly'.
     

    Attached Files:

    Last edited: Aug 1, 2020
    AlainK likes this.
  12. AlainK

    AlainK Renowned Contributor Forums Moderator Maple Society 10 Years

    Messages:
    3,621
    Likes Received:
    5,192
    Location:
    nr Orléans, France (E.U.)
    Thank you very much: bookmarked.
     
  13. JT1

    JT1 Contributor 10 Years

    Messages:
    1,395
    Likes Received:
    425
    Location:
    Euclid, OH USA
    @0soyoung thanks for sharing! Just scratching the surface of the provide information and I look forward to further reading, but wanted to extend thanks and appreciation at this point.
     
  14. AlainK

    AlainK Renowned Contributor Forums Moderator Maple Society 10 Years

    Messages:
    3,621
    Likes Received:
    5,192
    Location:
    nr Orléans, France (E.U.)
    Out of curiosity, I had a look at Index of /documents/diseasetrees, which is the "Index of /documents/diseasetrees", and there are 64 chapters!

    I'm also very grateful to all these people and organisations that share their work, their research, their knowledge.

    Including all the members who contribute here... That's how it should work everywhere ;)
     
    JT1 likes this.
  15. 0soyoung

    0soyoung Rising Contributor

    Messages:
    283
    Likes Received:
    364
    Location:
    Anacortes, WA
    I didn't previously say anything about verticillium propagation/reproduction, since we have been trying to analyze the OPs worries. But it seems quite relevant to our continuation of this thread to do so.

    Even though there is the possibility of transfer of the fungus by root exudates from one plant to another, verticillium spreads by microsclerotia in the soil. Figures 5-12, pp 41-51 of 'The Effect of Soil Moisture and Temperature on Survival of Verticillium Microscleratia'.

    It is actually difficult to sustain verticillium under common home gardening practices (or maybe this is why good gardening practices are what they are)!
     
  16. AlainK

    AlainK Renowned Contributor Forums Moderator Maple Society 10 Years

    Messages:
    3,621
    Likes Received:
    5,192
    Location:
    nr Orléans, France (E.U.)
    Another great resource, Thanks "Osoyoung".

    I confess that I won't read everything, my lack of knowledge means that I would only understand the parts that are some interest for me and that I will concentrate on.

    But at least, both theses use Celsius degrees, that saves me the time of checking with a converter ;).

    There are excellent references here, maybe they should be put in a subforum of "Pests and diseases", it's such a knowledge galore...
     
  17. Afterglow

    Afterglow New Member

    Messages:
    29
    Likes Received:
    2
    Location:
    Tyne and Wear, UK
    Hey Rosy

    I don't think you need to worry, and I think you answered your own question with your reply of how your trees were affected last year and how they are doing better this year, the leaves on your Shirasawanum Jordan is common on some of my trees in my garden, some varieties are prone to the wind shrivelling the leaves, some trees worse than others. Our Shirasawanum Yasemin has leaves like this in places too, spring till June, then the problem seems to stop, the winds in those months seem to do more damage than summer/autumn, maybe it's the temperate + winds, or leaves are young and more susceptible than toughened leaves by July onwards, just guessing through my own experiences.

    Your other 2 photos... I'm not an expert like the other members here, but those leaves look like what sometimes happens to my trees too, my little Shirasawanum Moonrise was putting out some new leaves a few weeks ago, we had heavy rain for almost a week, plus winds too, so the tender new leaves at end of the branch looked just like yours, almost 2 weeks later, those leaves continued to grow, but are damaged with pieces of the leaf missing.

    It only takes one small branch which dies to have several leaves, all dried up, my very full Acer Katsura has this right now, the rest of the tree is perfect, plus as you say, your trees are quite exposed, so I think you have to expect a little damaged now and again, throughout the year.
     

    Attached Files:

Share This Page