Help! I have several maples with light bark that are showing this black fungus like disease. I have tried phyton 27 during bud break and at the end of the year....but it has not stopped the progression of the blackening of the bark. It is not hurting the growth or the buds/leaves...but it sure looks bad and is getting worse.....especially on tsukushigata which is shown below. I sure hope that its not verticullium. My maples have very good air circulation.....but do have several conifers and birch trees in the area. Any ideas????
Hi Cirque, Are there any (possibly dead) branches where the buds do not open?, the ones in your picture seem to have healthy buds. Gomero
Yes those dark patches do not look like any form of verticillium that I am familiar with. I would be curious to know if it could be a sooty mold or something on the surface of the bark. Many of my maples have similar patterns of mildew or something that wipes off when you scrub it with a soapy paper towel.
I also wondered if it was something on the surface of the bark, it certainly looks that way from the photo. If you are going to try wiping it off might I suggest a microfibre cloth as the tool to use.
