I have 2 Shamel ash trees that are mature and have been generally healthy. They are about 14 years old. Every year i see growth and the new leaves are green and healthy. For some reason though, the leaves begin to yellow and die off as the heat of summer arrives. By summers end half the leaves are gone and the rest are mostly yellow. But by February new leaves are back, green and healthy. I have deep watering tubes that water to the roots that were installed when the trees were planted. This problem only started a few years ago. I do use moon juice per the instructions. I have seen garden plants and other plants suffer from to much salt in our soils. It looks like this may be the issue with my trees. Is there anything I can use to combat the salts? Gypsum?