Kigelia africana as pioneer

In the early days of the global village on earth, trees started to migrate with people. They took root in foreign places all over the earth where there leafy kith and kin were quite unknown. Companions to people seeking new homes, they were honoured, used or maligned but all of that is a long story.

Part of it is the list of reasons why people plant trees in new settings, away from their natural origins. Soothing memories of the fatherland left behind is one reason for nurturing and treasuring trees in faraway places. Timber, shade and aesthetics all feature too. Curiosity brought a practical reason in the arboretum idea of testing trees in new environments.

Arboretums are today natural laboratories where trees are assessed for adjustment in other than their natural settings. These testing grounds explore botanical, forestry and related commercially significant factors, including temperature hardiness, drought response, soil adaptability, seed viability, growth rate and pest resistance. Arboretums are found in many countries, some associated with botanical gardens. There are also arboreta for particular tree families, like oaks, poplars, willows and pines. In South Africa, Kirstenbosch includes an arboretum. An arboretum is also a living museum showing people trees of the world they may never see in habitat.

Wherever a tree grows out of its natural setting, it tells people something of where it can also grow and how well it may perform. Invasive species tend to talk too much in this regard.

In the Caledon Wildflower Garden, far to the south of the country, this Kigelia africana, the well-known sausage tree, child of the Lowveld and subtropical to tropical African conditions, is successfully adjusted, flowering and fruiting. Maybe somebody still knows who planted it, with what intentions, and how long ago (Coates Palgrave, 2002; iNaturalist; Wikipedia).