Kousa Dogwood Trees
I planted a kousa dogwood tree about 4 years ago in my backyard. It was healthy and growing well until just recently. This spring tree looked great and leaves and blooms were great looking. Recently, after it bloomed, a lot of the leaves are curling up in a tight curl. Not sure what is going on as this has never happened before. I also have this same type of tree (planted at the same time) in my front yard that is doing just fine.
The outward appearance of curled leaves and yellow-brown edges is of heat or water stress. If you think the plant has adequate moisture for the weather conditions - excessive heat and wind increase water needs - then problems with roots may be the cause. This is a much more serious issue. Dogwood can get root rot or can developed cankers that impair flow of water to the leaves. Although Kousa dogwoods experience fewer pest problems than the native species, nothing is problem free. Here is a rundown of potential dogwood problems. http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/visual-guides/flowering-dogwood-problems.aspx