A tree shares one thing in common with a human being it's a living organism. And like all living organisms their life expectancy will depend on their environment in which they live. Trees living in open areas are more prone to damage caused by gale force winds. Young trees hit by the impact of gale force winds may become destabilised and fall to the ground. But old trees with well established roots can usually endure the brunt of gale force winds. This must be the case because there are plenty of old oaks that are still standing today. The average age of an English oak tree is seven hundred and fifty years. But ancient oak trees are rare in England because so many of these oaks were used to build war ships. For example it took a hundred to two hundred oaks to build one warship and the craft itself may have only lasted ten years if it was lucky. When a tree loses one of its branches it's the equivalent of a human being having a limb amputated, but of course for the tree there is on medical care available. The tree is wounded its heart wood is left open to the air and the curse of microscopic killer fungi spores. Once these spores enter the heart wood of the tree they then develop into hypha which resemble cotton-like strands, at a more advance stage in their development these hypha join together to form mycelium. When this mycelium is mature it will need to reproduce and so it creates a fungus from which the pores or gills of the fruit body will produce the next generation of spores.
There are several species of killer fungi parasites which share the oak tree as their host. Fistulina hepatica has the common name the Beef steak fungus. Since the winter's gale force winds of 1992-3 and the devastation it caused to hundreds of mature oak trees, this fungus in some areas has had time to form parasitical heavens. There are question marks regarding the period of time it takes a tree to show signs of it outwardly decline and its eventual fall. What is for sure is that a mature oak tree may begin its outwardly decline be losing its lower branches. How many years will this take ? Roughly from between twenty to forty or more years. Here is a quote taken from the Daily Star news paper dated 05.07.03 with the title "School Boy Crushed By Oak Branch." "Despite emergency treatment Nathan, of west Acton, died five and a half hours later from head, internal and chest injuries." The investigation carried out by the royal police couldn't understand why the branch had fallen on the child when there was no wind that day.