It’s arbour month and people are planting trees to celebrate. But here is something about trees that is both astonishing, and a bit creepy: scientists in the US are trying to work out if trees may be able to “tell” them that a dead body is buried underneath them.
It’s all happening at The Body Farm at the University of Tennessee. You may have heard of it. Its real name is the Forensic Anthropology Centre and it was established in 1981 to help investigators understand how a human body decomposes. All the bodies are donated by people who want to help science. Some of the bodies are buried, some left in the open, some in water tanks or the boots of cars – all to simulate real situations where bodies are found by investigators. One of the first things an investigator tries to establish is the time of death. That is often crucial to identify both the killer and the victim. Body Farm Researchers look at things like insect activity on the corpse, what kinds there are and how long after death they appeared. The Body Farm staff also train investigators from the FBI and other organisations. There are now seven body farms in the US, and one each in Australia and Canada. There are none in South Africa, as our laws don’t allow that. There are some really interesting results. Researchers at the Australian body farm found in 2019 that a corpse moves after death. They used time-lapse cameras to photograph a corpse every 30 minutes during daylight. Its arms, which had started off next to the body, moved over time and ended up sticking out from the body. They were surprised that the movement went on for the entire 17 months of their research. They think it was caused by the ligaments drying out. Before this, it would have been assumed that the position a body was found in was the same as it was at the time of death. So where do trees come in? Well, it is an idea from a plant biologist at the University of Tennessee. Being at the same university as The Body Farm, he started discussions with colleagues about whether trees where researchers had buried bodies might “speak to us” about this. Not so far-fetched, he says, as plants change their chemistry and biology in the face of changes in their environment. When bodies decompose they release nitrogen, which fertilises plants and causes the leaves to become greener. Could they fly drones over wooded areas looking for that greener tree whose leaves may be “telling us” that it has a body buried underneath it? It is early days still, but the scientist hopes that within two years he will have a better understanding of “what trees and shrubs have to tell us about missing people, and learn how to ‘hear’ them from the air”. Got me thinking. If this technology ever materialises, could it perhaps find the remains of UCT drama student Rosalind Ballingall, who vanished without trace in the Knysna forest on 11 August 1969?
