Hello. I am very new to the forum. I dont know the specifics of the tree I have other than it is a Japanese Maple about 3 years old. It has been just fine up until about 1.5 months ago. I notice the leaves began to yellow, with no "dying" marks on them. Then they began to fall. About 2 weeks ago I found the damage on the trunk as seen in the pics below. A new limb has sprouted just below the damage as seen as well. Those leaves are reasonably green and seem healthy. We have had some heat though it has had water. I do remember the tag when purchased that it was full sun friendly as well. The upper limbs still seem to have moisture, as they flex easily. We purchased this one due to its brilliant red trunk and the strong green leaves contrast. I hope someone has an idea what is going on. Thanks!
Hello Sergei, Looks like a little Sango Kaku (or similar). Very prone to bark problems and drainage issues. It appears to have had problems near the base in a previous year and tried to recover. That's shown in the "lips" of bark around the wound in your first picture. This was likely an attack of pseudomonas. Now the already weakened tree has had further issues, again likely pseudomonas, around the base, which has "ringed" the bark of the main leader. Once this happens the effected area cannot recover and should be pruned off. Since there isn't much left, I would recommend replacing the plant. I have found "Eddisbury," another similar red-barked cultivar, to be less sensitive to this sort of problem. It's hard to see whether the new growth is coming from above or below the graft, if below it will eventually turn into a regular green Japanese Maple (without red bark). If above you could eventually coax it into growing another SK, but more likely the problems (for which there is no known effective treatment) will persist and it will die anyway. Sorry to be the bearer of bad news, but HTH. -E
