Japanese Maples: Japanese Maple Shedding Leaves, 1 by thumbless

thumbless wrote:
I have an 8yr old, approx. 8ft high Japanese Maple that was transplanted 2yrs ago. I lost a few small to medium branches the past summer and it appeared to be doing well. We've had tons of rain this spring but recently 2-3 weeks of hot/humid weather. Now it's slowly loosing leaves from the branches that are adjacent to the ones I pruned in the winter and creeping to a main branch. Is this a watering, fertilizing thing? Should I prune the branch that the leaves are falling off? Will the branch come back? What's going on? Just prior to the hot weather, I emptied a 12x3 ft pool that was 1/4 full of algea'd water. Could this have done in the tree?

Pic to maybe help.