My mother has a 20 year old ficus tree which is in front of our house. It has an ark in the middle as to make an entrance. About two weeks ago on one corner of the ficus tree, the leaves started drying and falling. Now the whole part of one side of the ficus tree is dried. Attached is a picture. What could it be? For 20 years it has never have had this problem. By the way the power cable on the picture are not crossing the ficus tree. These cables are on the other side of the street.
The other side of the ficus tree is very beautiful green. No sign drying.
Is it two trees with a trunk on either side? If that is the case, check to see if there has been some damage to the dying side. Perhaps one side is under more stress for some reason and its natural lifespan is nearing an end. It would be a shame to only have half an arch until a new tree can grow into its spot. More information may be needed for a good explanation and solution.