With the plight of rhinos having garnered an international outcry, it is hard to imagine any other species receiving more protection by armed guards. But the humble pepper bark tree, now almost extinct in its natural habitat, is fighting for survival. With the help of a group of tree experts, this African gem can be protected from possible extinction.
The pepper bark is the only known tree under armed guard in a protected area in South Africa. Also known as the Warburgia salutaris, it was once widespread in southern Africa, but today it is rated as endangered by both the International Union for Conservation of Nature and the South African National Biodiversity Institute (Sanbi) and is one of the specially protected trees with the Department of Forestry.
This tree’s greatest gift has unfortunately led to its demise, as its medicinal properties are highly sought after. The pepper bark, known for its pungent inner bark, is an evergreen tree that grows to between five and 10 metres in height. The numerous ailments that can potentially be treated with this species include fever, malaria, influenza and coughs and it is a natural antibiotic for chest infections. The tree is also used for the treatment of abdominal pain, constipation, cancer, rheumatism, urinary tract infections and stomach ulcers. It is applied topically to cuts, on the temples for headaches, and has been used as an aphrodisiac. More recently, it has been used in the treatment of HIV. Many of the medicinal claims of the tree have been scientifically confirmed and is therefore sought after by western homoeopathy for a number of ailments.
Unsustainable poaching of components like bark, stems, roots and leaves have resulted in wild populations being placed under extreme threat. In South Africa, the species is predominantly found in protected areas and as ornamental trees in domestic gardens, with a small number of trees secretly found in their natural habitat.
A Warburgia Working Group, consisting of scientists and naturalists from Sappi, the Agricultural Research Council in Mbombela, Sanbi Mbombela, SANParks and Twin Streams Nursery, who believe in the value of this tree, has created a project to invigorate wild plantations and educate communities about sustainable harvesting of its components, while still enabling it to flourish. The Warburgia project propagates seedlings for distribution and provides educational workshops at no charge in communities where the tree has been eradicated. It is also hoped that the wild populations will regenerate themselves naturally once not under direct threat and stress.
The tree propagates well from fresh seed, but it is challenging for it to grow from cuttings, and in the wild, under stress, it holds back on seed production. Seed production is also low, and both the fruit and the seed are hosts to the larvae of a fruit fly species that causes immense damage and loss.
Through the working group, these challenges have been resolved to a greater degree. Gene banks and seed orchards have been created and to date over 30 000 seedlings have been grown. Through the project, it has become acceptable to use leaves and twigs harvested from trees as young as four years old, thus not having to wait some 15 years to harvest the bark.
Sappi’s expertise with growing trees has come in handy in the project and trials with cuttings rooted and transplanted into five-litre bags have proven successful. These are then distributed to communities with information on how to care for the plants. Sappi recently provided 1 025 pepper bark trees to their staff and surrounding schools to be planted in their communities. They aim to produce around 10 000 plants per annum for distribution into the environment and are also planning the establishment of a two-hectare seed orchard for the conservation of the species, where seed may in future be harvested.
The success of the project has also seen its expansion into KwaZulu-Natal, Kingdom of eSwatini and Zimbabwe.
Further value from the project is that an easy working template has been developed for endangered trees that are a challenge to grow. To this end, work will soon commence on a project to conserve the Prunis Africana or red stinkwood.