To answer that question...............deep root injection if possible.! Slow release......fert! Low Salt content!!
Near a group of church's here, there is a Oak tree that is more than 20' in circumference and was subject to limb removal from a storm years ago. The problem with this tree is it is a part of the down town historical society and is a part of nostalgia. It has a wonderful aesthetic value!!! There is pavement, concrete, and busy streets that encircle the entire CRZ.........so the tree was Mauget Fertilized by another Arborist. The tree is still doing fine but only time and weather will tell. In this case--deep root injection wasn't an option as it was not in the best interest of the tree to have encircled the CRZ with all those roadways. Just a couple years past, during another storm, a large oak fell in this same area from straight line winds............fell on a parked car at a red light with mother and infant inside. The jaws of life had to be used to extract the infant and mother. Happens everywhere I am sure. Decayed roots and restricted later rooting and hard soils were to blame. Anytime you go through a severe drought season...........the soil hardens and other places become powdered. Heavy rains along with sudden dounburst winds can sway trees from their already weak soil penetrated miserable surroundings. It has no where to go but down!!!