Q.Japanese maple dying
Tree is seven yrs old. Has some black oily looking spots and some tiny pin holes, and what looks like white poop of some insect. I only see that on the side of the tree that has died. Some branches are still alive. I scraped in spots and a lot of the tree is dead hard wood. Is this tree confused – half alive and half dead? The dead parts started to flower just fine and then withered.
Examine the leaves for signs of insects. They produce honeydew which in turn attracts sooty mold.
When they are located, spray once a week with an insecticidal soap or horticulture oil. Sooty mold will die off when it's food source disappears.
Here is a link.