I live in Abu Dhabi, UAE. I've had a lime tree for 14 years. It bears fruit every year form April to July. However, limbs have been dying off for a few years now. I have cut off the dead wood but other branches then die off. It now has nothing but dead branches on top and new shoots growing around the bottom of the trunk. I don't know what to do and gardening help is difficult to get. The climate is warm all year, daytime temp. up to 48 C in summer and down to 18 C in winter. Nighttime temps can fall to 5 C. Hope you can help.