Hi everyone. Attached find photos of two of my maples. They seem to have developed some kind of spot blight. Questions: What is it? How do I cure it? Thanks in advance!
Could be a sun scorch if it was watered in direct sun. My wife got some overspray on a large dissectum and it's got similiar colloring, but not spots.
I am thinking that it may be a fungus problem. We have had a particularly wet spring here in Connecticut and I have had a layer of chips over the roots since April. Do you have any suggestions as to the right anti-fungus agent to use?
Every year I have many A. palmatum cultivars displaying the same condition. I do not now what it is. I know it is not sun scorch. I have tried several anti-fungal sprays but to no avail. Now I do nothing, it is unsightly but it does not seem to affect the overall health of the tree. Gomero
I have about 200 Japanese Maples that border my property. Some get this, others do not. The ones that do get it are in a more shaded area, and because we have had a lot of rain this season, I am guessing that it some kind of fungus combined with having wood chips at the base of the trees. So one solution is to pull back some of the chips now, cut back on the water (of course, it is raining today), and maybe try some kind of anti-fungus spray. I also added peat moss at the base too so that the crown is protected. It may also be a consequence of the fertilizer that I have been using, or the insecticide for the beetles. Just don't know. But I do know that it happens to some and not all, and happens more frequently to the shaded trees. I do suspect that it has to do with the dampness of the wood chips at the base and the wet weather. Any thoughts on a good anti-fungus agent?
Cannot help since trade names are not the same in both sides of the Atlantic. Please keep us informed if you succeed with your treatment. Gomero
I will. If we have the same thing going on, check the amount of mulch you have above the crown. And then monitor the dampness. We cannot do much about the rain, but we can control the water and the tinker with how long the soil stays moist. Thanks for your comments.
No, sorry, maybe a Google search. It's mentioned here www.botanicalgarden.ubc.ca/forums/showthread.php?t=16485
Another disease , Phyllosticta Spot, and control using bordeaux mixture are described here http://agnic.msu.edu/hgpubs/modus/morefile/hg81_72.pdf. Apparently the mixture is also used to control anthracnose. Suppose a plant pathologist might be needed to verify either disease.
I cannot draw any correlations since the affected maples (and they tend to be always the same) are in very different conditions: in the ground or in pots, sun or shade, heavy or light mulch. It is true that for a while I thought it was antrachnose but since the recommended treatment for that condition did not work, I am no longer certain. Gomero
I don't think so because it only effects a few of the japanese maples in my yard. The ones that have more sun (i.e. are more dry) do not have this condition.
Just to play devils advocate... If it were acid rain then perhaps some maples have leaves that are more sensitive than others and the ones in shade probably don't dry out as quickly so the water droplets stay on the leaves longer giving them more time to affect the leaves. Could explain both why trees next to each other in same growing conditions don't get it (one is more sensitive than the other) and why there is a higher incidence in the shade than not (longer time to burn the leaf). BTW, 200 maples bordering the property? Oh, my that must be beautiful!
Anything is possible. Could be acid rain. Yes, 200 or so, could be more. Most of them are small so they are easy to manage at this point. In about 5 years they should be something special to look at. I need to move the aureum though - too much sun.
Saw this Sagara nishiki at a local nursery and thought of y'all. It's also in almost full shade. We haven't had any rain for it to be acid rain. I don't know their watering practices but somehow I doubt they water the crowns of their trees. But it just looks like water sat on the leaves too long. Hmm. What could do that?
I'm relatively 'new' to maples, but not gardening. Could this be an insect issue such as leaf miners? Skeezix
Winterhaven, I believe what appears in the Sagara Nishiki leaves is a different problem that that shown in the pics of Gerard. If you look at the 'Akane' thread in the Gallery you may see some similarities to what you show. Gomero
Looks like no big deal to me. I've seen spots like that come and go around here. There are reams of variations for night time or day time temperatures combined with moisture, dew or raindrops on leaves. Some conditions at the right time enable fungus or bacteria to develop more abundantly. At times, it can cause some spots. Comes and goes. Not worth spraying for the way I look at it. The smaller the tree, the more noticeable it seems to be. Overall, the tree looks pretty good.
I have had spots like thse on my maples on and off, depending on the weather conditions. It seems to happen when we have had a spell of very wet windy weather followed by dry. So far it hasn't proved fatal :)