"Mighty" is a much used adjective for oak trees, all the more so when it's a newspaper story about disaster. "Mystery Disease Fells Mighty Oaks" (Daily Telegraph, July 27th), and then a story from the American South "Termites Haunt, and Topple, Mighty Oaks in Leafy New Orleans". "That was June 30th this year, in the New York Times.
Their trouble is known as die back. The tree thins at the crown. The balding process may be progressive, the leaves falling off. Then various insects take advantage. There may be recovery, but slow. Or complete defoliation takes place, and death within two or three years. The article says that there have been five international discussions on the disease in the past decade: in Austria, Poland, Hungary, Italy and France. A forest pathologist, Brian Greig, is quoted as saying that the number affected is not great. He thinks it is unlikely to be contagious, as one tree in an area may die, but the others remain untouched. Still. It may be that climatic changes make the oaks vulnerable, dry summers and winter cold air pollution and other factors contributing. There is some consolation in the fact that a dead, recumbent tree is good news for various insects and some mammals, even. Britain's prize concentration of oaks is in Windsor Great Park. Dieback then tends to affect the younger trees, the article tells us; that is, those between 80 and 150 years old. Their seniors of, say, three or four centuries are, according to one Dr Keith Kirby, untouched. As to New Orleans, the trouble comes from Formosan termites. Termites are often known as white ants. Oaks are a great feature of the city ". . . lush, ancient, majestic trees that grow so thick on some streets that they form tunnels of dark shade for blocks and blocks . . ." They look healthy, says the director of their Parks Department, but according to the story, a few months ago a pest exterminator parked his car outside a house to talk to the owners about their termites inside. There was a loud crash shortly after, and he came out to find that a huge branch, weakened by the termites had fallen and smashed his truck.
That's what happens. A tree may look fine outside, but it has been hollowed by the bugs and no one knows when a branch will crack and drop. One tree in seven may be affected; some say one in five. And the termite first landed, it is believed, on ships coming from the Pacific in the second World War. They eat up from the roots. But officials are working on the problem. Some of their trees are 500 and 600 years old, said a city entomologist, who hopes still to defeat the bugs. Regarding anaphylaxis in the content of bee and wasp stings, this may arise also from other causes, hyper reaction to peanuts for example. The doctor will often advise, in such cases, that the antidote be carried at all times in a syringe for instant use.