I am trying to figure out what is going on with the leaves on my tree. They get light spots within the leaves that turn brownish and the leaves drop. This is a potted plant in NYC. There is not too much of a symptom on the top side of the leaf except a little wrinkling. One photo is with the light behind it to highlight the issue any thoughts as to the cause? Edema seems the most likely but I don't want to let it go if something else. I don't see any signs of scale or mites