Japanese maple issue
This looks like symptoms of cold damage and we are receiving photos of Japanese maples like this from all over the state. Many plants were lured out of dormancy and then were hit with frosts and cold temperatures. On some trees we are also noticing damage on the top growth versus the bottom growth. This may be due to warmth from the ground area and bottom growth was not affected. The damaged leaves eventually drop out. If the tree is otherwise healthy, it will push out new growth this spring/summer. No treatment is necessary.
Keep your tree well watered during dry periods and make sure mulch is no thicker than 2"-3" inches deep and kept away from the trunk. You can send us more photos this season, if you notice additional symptoms.