CIRCLE OF LIFE IN A FOREST
Updated: Oct 12, 2021
Vachelia robusta and Senegalia caffra are the most common Acacia trees at Melville Koppies in Johannesburg. However, there are some huge, fast growing Vachelia karroo trees too, in places where there is a good water supply. It seems that clusters of these trees were planted on the banks of Beyers Naude Drive bordering the Westdene Spruit in the 1960s, after Melville Koppies was proclaimed a nature reserve.
One V.karroo was planted near the top of the Koppies at the Kafue Road entrance and this towering tree thrived on stormwater run-off from this road. One day a strange fungus was observed at the base of the tree, but it continued to flourish. Professor Konrad von Warmelo, a microbiologist, said that the tree was doomed and the fungus was just the fruiting body of a saprophytic Ganoderma lucidum. The rest of the fungus had already permeated the entire tree.
In 2012, a howling wind ripped through the koppies and the doomed tree keeled over, smashing onto the forest of smaller trees. The dead tree presented a dangerous fire load and this was gradually reduced by the carefully controlled burning of branches. In due course just the massive trunk was left, which saprophytic fungi eventually reduced to dust. These fungi are an essential part of the circle of life in a forest. Other indigenous trees, but not another V.karroo, have since flourished where the giant fell, thereby completing this particular circle.