Kokerboom trees are adapted to desert climates, but the water shortage in the wake of climate change makes stocks dwindle.
This text was originally published in Swedish in the magazine Sveriges Natur issue 2 2014.
You might expect specialized desert plants to withstand a warmer and drier climate better than others. But it is not necessarily so. The researchers see the strange kokerboom tree as one of the most obvious examples of how the lack of water in South Africa today is threatening unique plants and ecosystems.
Last autumn we visited the area around the small town Nieuwoudtville in the Northern Cape for an article about Rooibos tea and Climate (published in issue 5/ 13). One evening we drove through the desolate magnificent landscape to see South Africa’s southernmost kokerboomforest . Though forest … as Scandinavian you find it hard to think of the large succulents spread out unevenly over the rocky mountainside, or forming a crooked parade along a narrow ridge against the sharp blue sky, as a forest.
In Latin the name of the plant is aloe dichotoma, in English they are called quiver trees. The name derives from the San peoples’ usage of branches as quivers for their arrows. The thick stems and starpatterned canopy looks dramatic in golden and brown tones. Up close the size impresses. Some of the trees are ten metres tall and up 250 years old.
Scientists at the South African Institute for Biodiversity notice an increased mortality in the northern range of the trees, a trend which agrees well with the climate change predictions . But persistent giants will not move so easily, and now stocks are going down. A trend the quiver trees share with many of the species in the dry Karoo vegetation type. 40 percent of them are endemic (found only here).
Plants are affected, but South Africa’s growing water stress is already causing trouble also for people. Especially the poorest. Read more about the effects of the water shortage in the large township of Kayelitsha here.
Text and photos Mats Hellmark