Hey all, Looking for help treating a trunk turning black on a recently acquired Sango Kaku. This is the second Sango that developed the issue under my care this season. Some background, the tree dried up a bit a few weeks ago after purchasing. I have since slip potted it into a better mixture and moved it into the shade. Located in zone 6a. tia
@Nismo0921, good afternoon and welcome to the maples forum. Looking at your photos IMO this could be Verticullum wilt. There is no effective treatment for this I'm afraid. Did you purchase both trees from the same supplier ? As Verticullum is soil borne, it may well be in all the trees from where you purchased it from. The soil also looks overly wet which is not good if it is not draining well. Was the growing medium free draining and did you use the same mixture the last one you lost was in ? By that I mean the same bag of compost etc. That could be another clue. Was the same pot used, did you clean thoroughly before re using? Was there any blackening of the upper stems of the branches when you noticed the loss of leaves as that can point to Pseudomonas syringae which is an air borne bacteria. A very wet Spring and a wound can cause this problem. This though can be treated with copper sulfate spraying at the top and a soil drench. Others may have a different opinion, but that is what I am seeing. Sorry to ask so many questions of you, but your answers may give a better picture of your trees problems.
Hey D, thanks for the reply. The picture was taken as I was watering the tree which is why It looks wet. I used pine bark mulch and perlite when I slip potted and yes, they were both purchased from the same nursery, neither one had black bark when I took them home. They swapped the first one for the second, but I wont ask them do so again. Any chance this will heal on its own? I was thinking of putting this tree into the ground once the heat lets up a bit.
@Nismo0921, tbh I would return it, as IMO it probably has Verticullum wilt. It will not get better. The clue was the same supplier. If you do return it, do dispose of the compost and not tip it in your garden as this is soil borne and do wash the pot out if you are going to use it again. I use a diluted bleach for this then rinse thoroughly. Do not be put off from this experience, it happens to us all at some time. But do go to another supplier and post a photo of your new tree.
