Rare Plant Species Focussed On In Management Plan
In line with the protected areas act, the Kruger National Park (KNP) has been busy drawing up a park management plan that will guide the park's management priorities over the next five years. The main guidelines to managing the park fall under the banners of biodiversity, human benefits, wilderness, constituency building and cultural heritage.
Under the banner of biodiversity falls the conservation of species that are threatened with extinction. Five species that live within Kruger's boundaries fall into the highest risk categories of global extinction, and these are highlighted as being of particular concern in the management plan.
These key species are the black rhino (Diceros bicornis), the wild dog (Lycaon pictus), the pepperbark tree (Warburgia salutaris), wild ginger (Siphonochilus aethiopicus) and the Swazi impala lily (Adenium swazicum). All of these species face the threat of increasing habitat destruction, but only the wild dog is not faced with destruction at the hands of traditional healers around the world.
With so much attention placed on mammals, it is important that plant species not be forgotten in ongoing conservation efforts. The twin prongs of habitat loss and the muti trade are rapidly driving the plant species listed towards extinction, and Kruger's populations represent a remaining stronghold for the future of the three species.
The Swazi lily, a cousin of the ever-popular and much more common impala lily, is probably the least threatened by the muti trade but the most threatened by the loss of habitat. The Swazi lily is very similar to the impala lily, looking a bit like a baby baobab with its smooth grey stems and bulbous base and roots, but it flowers in summer, rather than winter.
The flowers are a similar shape to those of the impala lily, but are completely pink rather than pink and white. The Swazi lily has a relatively small historic distribution range, growing mostly in Mpumalanga in a strip between Swaziland and the Kruger Park.
According to botanist Janine Victor at Sanbi, there is strong evidence that there has been an 80 percent decline in the Swazi lily population over the last 60 years, putting it in dire threat of extinction. This is mostly due to the development of extensive sugar cane farms between Swaziland and Kruger, which have almost wiped out the plant's natural habitat. The plant is used, along with the impala lily, for magic potions and for muti. Latex from impala lilies is also used as a fish poison.
Wild ginger is distantly related to ordinary ginger. It grows in many African countries, but in all of them it is threatened because it is so highly prized as a medicinal plant. In South Africa, it was mostly found in KwaZulu-Natal and Mpumalanga, but is now extinct in KwaZulu-Natal because of harvesting for the muti trade.
Just like with ordinary ginger, the roots and other underground plant material are harvested. The plant loses its leaves in winter, pushing up new leaves that look a bit like a young mealie plant in spring. It has spectacular flowers, which occur at ground level. These flowers are very shortlived, look a bit like orchids and vary in colour from bright pink to white with a yellow centre.
Wild ginger plants can either be female or male, with female plants being smaller than male or bisexual plants. According to Prof Neil Crouch, a medicinal plant expert from Sanbi, wild ginger is one of the most expensive muti plants on the market.
The thriving trade in wild ginger means that many of the remaining populations lie in protected areas, but they are still threatened by plant thieves in some protected areas. Crouch says "It is clear that the species is diminishing in South Africa, with only about 2,500 plants known to still occur in the country." This highlights the importance of protecting the plants in places like Kruger.
Attempts to grow wild ginger as a crop have been made, but Crouch says that is has proved difficult to engage with the market place and growers have not made as much money as they expected. The wild ginger plant is used to treat asthma, coughs, colds and flu. It has also been used to treat hysteria, menstrual pain, malaria, and is used by the Zulu people as a charm against lightning and snakes. It has been also used to prevent horse sickness.
The Pepperbark Tree
In terms of extinction threat, the pepperbark tree is probably the least threatened (in global terms) of the three species listed in Kruger's management plan, but has been heavily harvested for muti purposes in South Africa, and is almost extinct in KwaZulu-Natal. It has a very limited distribution in the park, and was also found in limited areas in northern KwaZulu- Natal, Swaziland, Mpumalanga and Limpopo, usually in forests and wooded ravines.
It is found in other African countries to the north of South Africa. It is a medium-sized tree with glossy green leaves. The bark of tree is rough and mottled, with a reddish inner side and a strong peppery taste. The bark is harvested and used to treat coughs, colds, and other chest problems, as well as malaria.
As Sanbi expert Janine Victor points out, it is harder to re-colonise natural areas with trees and plants than it is with mammals. This adds increasing importance to Kruger's populations of these rare plants in the face of unsustainable development and illegal plant harvesting around the country.
In order to manage their populations of rare plants, Kruger has decided on thresholds of potential concern (TPC) that will be triggered when surveys reveal that the populations of the plants are declining or have a skewed population size/age class distribution.
A further TPC is reached when five percent of the reproductive individuals have been impacted on in a way that affects their regeneration, an interesting point to bear in mind there are stories about how elephants have a taste for wild ginger and use their good sense of smell to find the plant and dig it up for a good meal…and that means 12,500 potential wild ginger harvesters that are legally operating in the park.
By Melissa Wray
In Kruger National Park