The Lost Fynbos of Tokai Park
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The lost fynbos of Tokai Park by Anthony Hitchcock, Nursery and Threatened Plants Programme Manager, ABOVE: Paul and Liz Johnston, Anthony Hitchcock, Eric Harley and Tony Norton with the Erica verticillata plants that were successfully restored to the Prinskasteel wetland in Tokai. Kirstenbosch National Botanical Garden, Carly Cowell, Regional Ecologist, Cape Photo: Tony Rebelo. Research Centre, South African National Parks and Tony Rebelo, Threatened Species Research Unit, South African National Biodiversity Institute he restoration of Tokai represents one of our last environmental expiry date. It also means that thousands of plants opportunities to link ecological processes from Table can be grown, rather than a dozen or so in a tight space in a botanical TMountain to the Cape Flats, as well as to rehabilitate a garden, thus allowing the development of robust gene banks that sustainable area of critically endangered Cape Flats Sand Fynbos. are capable of dealing with variation and change in the environment. The biggest threat to our natural vegetation today is habitat Restoration is however fraught with challenges. The more an destruction. It is crucial to the restoration of threatened species area has been transformed the more difficult it is to restore it. that we secure natural habitats for their survival. The alternative Restoration of old farm lands, for instance, is problematic as the is keeping small collections in botanical gardens, such as soil structure has been destroyed and the indigenous seed banks Kirstenbosch, or as vacuum-packed seeds in temperature-con- lost. Areas invaded by alien plants are easier to restore as often the trolled vaults, such as at the Millennium Seed Bank at Wakehurst soil is still intact, although if the invasions have been prolonged, Place in England. The problem with these is that a single event the indigenous seed banks may have died. In pine plantations could destroy a collection: a power failure, lack of watering over where the seed banks have not yet been lost, restoration can occur a weekend, an accidental application of herbicide instead of by just removing the pines and clearing the debris with a burn. insecticide or a thermostat malfunctioning. An inexpensive valve Fire is essential for fynbos restoration. It not only clears the debris, or a misreading of a label could wipe out an entire collection of but also sterilizes the soil, eliminating pathogens and predators, irreplaceable plants and animals. and cues the seeds to germinate after the following rain. It is far more efficient to restore a patch of veld and return the Habitat restoration is thus multi-factorial. It includes restoring threatened species to their natural environments where they can the soil structure, clearing alien invasive species, burning to interact and evolve with their pollinators, dispersers, predators and stimulate regeneration, restoring the balance of fauna, flora and physical environment. At least that way the species can track and fungi, and allowing the ecosystem to take over and restore itself. adapt to climate change and other environmental changes which The primary objective of restoration is definitely not gardening. they would not be able to do as domesticated pot plants or as seeds Instead it is to kick-start the ecosystem to look after itself with maladapted to local conditions by being decades beyond their minimum further intervention. 30 VELD&FLORA | MARCH 2012 Research has shown that after three the seed banks to germinate. To this end using herbarium and Red List monitoring generations of invasion, seed banks are lost. a restoration burn is essential. However, records – the nearest surviving population The shorter-lived seed banks are lost early, but we know that the serotinous species that might be a source for seeds or at three generations the bulk of the species do not have a seed bank and will thus propagation material. In some cases, the have gone. Among the first to disappear are have to be re-introduced. This is best nearest (and last!) surviving populations the dominant and most prominent species – done by sowing seeds onto the postfire may be as far away as Somerset West, as those that store their seeds on the plant and environment before the first rains. We is the Shy Watsonia (Watsonia humilis) release them after a fire – like the charismatic suspect that re-sprouting species, which with a conservation status of Critically sugarbushes, conebushes and brunias. These tend to have small seed banks, will require Endangered, or Rondeberg up the West species will need to be returned to restore augmentation as very few seeds will Coast in the case of the Slack Buchu functioning ecosystems. survive to germinate. We also know that (Agathosma glabrata) which is Endangered. The animal communities are easier as the the alien seed banks (like the Australian Tokai is the only ecologically viable majority of them will return when the plants wattles) will be large and alien control is conservation area of Sand Fynbos in the are restored, assuming that some natural therefore essential. southern suburbs. Other areas exist, but habitat remains not too far away. These are The restoration at Tokai thus requires the are too small to survive without intensive essential for pollination, control of more co-ordination of the tree fellers to minimize management. Consequently the area is the vigorous plants and animals, and a myriad damage and clear the area in time for an major potential restoration site for other of interactions which fine-tune ecosystems autumn fire, the fire teams to burn before highly threatened species. A list of fifty allowing them to deliver their services. the first autumn rains, and the alien teams of the most threatened species from the to clear the emergent weeds. At the same Cape Flats has been compiled for potential Restoration at Tokai time horticulturalists need to collect seeds restoration. The Tokai section of the Table Mountain for release and sowing after the fire and National Park, fortunately, appears to have to prepare cuttings for planting when Process and timing been rescued in time. Tokai is at the third sufficient rains have fallen. Species are collected as seeds or generation cusp – rescued at the final There is only one problem with this cuttings, and germinated or rooted at the cycle while the last of the seed bank is still scenario. In the hundred years since Pur- Kirstenbosch nursery. These are ‘grown- intact. We are also very fortunate in having cell compiled his list, many species have on’ in small bags or ‘unigrow’ plugs and a comprehensive plant species list from a become threatened with extinction, kept separate from other collections in neighbouring farm, Bergvliet, collected by mainly due to habitat loss. In fact, 35 of the nursery. Unigrow plugs are hard, William Purcell from 1915 –1919, so we have these species are listed as threatened on narrow plastic sleeves that allow deep a reasonable idea of species that might the Red List, with three extinct in the wild. root growth in minimal growing medium. have occurred in the area. Furthermore, Obviously the extinct and most threatened The healthy root systems ensure rapid Sybil Morris, a resident of Tokai, has been species top the list for re-introduction growth. The narrow plugs minimize soil monitoring plants regenerating under the to Tokai, provided that they don’t have disturbance, reducing the possibility of pines and in clearings, so that we have a emergent seed banks. To this end Purcell’s introducing weeds, alien soil animals good list of species that have survived in list was compared to the existing plants, and soil diseases. The plugs are sterilized the plantations. the Red List, known flowering (two and re-used. It is essential to time the The restoration of plant species at Tokai months later, for seed) and growth (two collection and regulate the growing so is therefore primarily that of encouraging months earlier, for cuttings) times, and – that the time in the nursery – where BELOW: Friend of Tokai Park volunteer, Eric Harley, planting a Mountain Dahlia (Liparia splendens var. splendens). Photo: SANBI. RIGHT: Waiting for the rain. Sarah-Leigh Hutchinson, FRD restoration intern at SANBI and James Forsyth, Friends of Constantia Valley Green Belt in the area where the plantations were cleared and burned. All that was needed was some autumn rain, but unfortunately, the autumn and winter of 2011 was exceptionally dry. Photo: Tony Rebelo. MARCH 2012 | VELD&FLORA 31 diseases and hybridization may occur – is kept to a minimum. The weather was not ideal with temperatures in the mid-twenties Plants must be ready for planting by winter, with a window for and the soils almost dry; having not had any rain for weeks. planting till mid July, after which plants will not establish before Proteaceae were planted early in July by the Friends of Tokai the onset of the summer drought. Park and SANBI’s Threatened Species Unit over the entire area, 2011 was the fourth year of restoration planting at Tokai. An area but especially near the paths. The wetland species were planted of 25 ha, the biggest area to be restored since restoration began, later in July by a team of Kirstenbosch horticulturists, nurserymen had been clear-felled and burnt on schedule. Although the first and the Protea Garden team assisted by the Friends of Tokai Park, fire was almost put out by rain, the rains then dried up. Seeds of the Kirstenbosch Plant Recorder and the Threatened Species serotinous species were sown in April, but despite the anticipation, Unit, in what is known as the ‘Lost Wetland’. The initial signs are winter did not arrive. By late July the end of the planting window positive. Although winter rains were poor, the spring rains have was approaching, and there was no choice but to plant out the been regular, if a bit scanty.