Dwarf Japanese Maple Problem
The leaves on our young dwarf Japanese elm (4') all turned red and wilted, despite adequate water. New green leaves did come out but now some just clump up and die. There are a few green leaves still. The elm is in a large pot. The top tends to stay dry and the bottom moist. We don't see any insects on the tree. The tree only gets direct sun for an hour or so in the early evening, since it gets so hot here (Bakersfield). My wife, who loves the tree, is so frustrated she's ready to give up. We replaced the outer soil (not original root ball soil) with soil that a local nursery said may improve conditions but we still have the problem. Any advice you could give would be greatly appreciated.
I would recommend double checking the roots. If there is root damage or rot, then this could be causing issues that would look similar to underwatering. If you can, check all the way to the bottom for mushy or damaged roots.
As a precaution, treat the tree with neem oil. It is both a fungicide and a pesticide. It is very hard to diagnose trees without examining them, but neem oil will cover many of the things that could be wrong with the tree.