Shaped by suffering” is how South African botanist Ernst van Jaarsveld described the aloes and succulents that have adapted to thrive in some of the harshest, hottest regions of the world.
The Aloe, Cactus and Succulent Society of Zimbabwe, the country’s own small group of enthusiasts dedicated to the study and survival of these species, held a unique gathering last month (June) of experts from all over the world to reveal their insights into some of the world’s rarer plant forms that Southern Africa is home to.
For two days at the Wild Geese Lodge just outside Harare, the audience of 65 at the “Xerophytica (plants that withstand drought) congress” heard of new research and developments into these unique forms of plant life, from cycads and baobab trees to cacti and the extraordinary Welwitschia mirabilis.
Ernest van Jaarsveld from South Africa’s Kirstenbosch botanic garden demystified the notion of the supposed slender survival chances of the weird Welwitschia plant and its dull green leathery leaves that extend for metres on the sands of the Namib desert. He got seeds of the plant to germinate in three days. He couldn’t explain, though, how fossils of the plant were discovered in northern Brazil.
Ben-Erik van Wyk, professor of Botany at Johannesburg University, spoke of the extraordinary success of the modest Aloe vera plant that has generated a medicinal industry of US$110 billion a year. The place of aloes in ancient medicine is revealed in the paintings of the San people (Bushmen) in South Africa.
The San also use the white latex of Euphorbia plants to fix arrow heads to their arrows, he said. To test the strength of the plant’s glue, he once smeared some in the back pocket of a friend’s jeans where his wallet was. It could only be reached by cutting it out.
Piet Vorster of Stellenbosch University in South Africa told of attempts to create a female partner for last survivor from the wild of the cycad species, Encephalartos woodii. Crossing the male seed again and again with another cycad species so that it eventually produces a plant that is genetically 99% woodii, he eventually got a single female seedling that, he hopes, will be close enough to be a partner to the lone plant in Durban.
Many succulent species in Southern Africa are faced with extinction for their value as muti. He described whole pick-up loads of the rare Namibian stone-like lithops genus being dumped in township muti markets, most of it left to rot.
The many species of aloe in the mountainous coastal regions Arabia are under even greater threat following a population explosion there, according to American collector Tom McCoy. Some species have been decimated by sheep that eat aloe flowers – leaving no seed. Tribesmen cut out the centres of other aloes to feed their donkeys.
Buhle Francis of the National University of Science and Technology in Bulawayo revealed a terrifying new threat, from the vicious barbed thorns of the Opuntia fulgida cactus, which she calls “the demon invader of the savannah.” The densely sprawling cactus from the deserts of Arizona and northern Mexico was originally brought by a Mr Harvey for his garden in the Tuli cattle breeding station in the sixties.
Known also as the “jumping cholla” for its ability to spread, and without any natural enemies, it has entrenched itself in large areas of south-west Matabeleland that are increasingly choked by the cactus. Birds, bats, snakes goats, cattle and donkeys are increasingly being found impaled to the spines of the plant, which cause horrendous injuries and slow death to animals.