The progress of the ZIMP Botany Group
(Extract article from the volume 2006/3 Newsletter)
An erica species that is extinct in the wild was propagated from seed for the first time last year, and this winter will see its reintroduction at wetland rehabilitation sites along the Prinskasteel River one of the catchment rivers which eventually flows into Zandvlei via the Keysers River.
The Cape Flats erica is somewhat finicky about where it grows, preferring to sink its roots into boggy ground on the fringes of seasonal wetlands. It's one of the showiest plants in the Cape Floral Kingdom, producing spectacular pink whorls sometimes 2 metres high in the midst of summer. And that's exactly why it's so extremely rare. The combination of its great beauty at a time of year when most fynbos species are drab, as well as its limited habitat, led to enormous pressures on the species from the flower industry until by the mid 20th century it became extinct in the wild.
It was in fact thought that Erica verticillata had become entirely extinct, but in 1988 Deon Kotze of the National Botanical Institute discovered a single plant in a municipal garden in Pretoria, and took cuttings - quite timeously as it turns out because the original plant died soon afterwards. The cuttings thrived and after some experimentation by Dalton Gibbs of the City of Cape Town to find the corrrect habitat, over a hundred were planted out into the Rondevlei Nature Reserve.
The erica is pollinated by hawk moths and Lesser Doublecollared Sunbirds but at Rondevlei it did not produce seed. A renewed search turned up another plant at Kew Gardens in Britain and another in Vienna. Cuttings were flown back to South Africa and the genetic mix encouraged seed production. But yet another crisis reared - none of the seed seemed viable. Not only were seedlings not growing in the wild but attempts by the NBI (National Botanical Institute) to propagate them failed.
Victoria (Vicky) Wilman with the 400 seedlings to be planted out this winter
And then Victoria Wilman came onto the scene last year and succeeded in producing the first generation from seed. At that stage she worked part-time for Working for Wetlands. For her horticultural diploma research project with the Cape Peninsula University of Technology she experimented with different growing methods for Erica verticillata. What worked best was a peat-sand mix and a special smoking technique.
Winning the Dean's Medal for Natural Sciences was a small reward compared to watching her 400 seedlings grow. Wilman says, "The plant will still be considered extinct in the wild until it produces seedlings and proves to have a viable population. It grows in a very threatened habitat but I'm optimistic about its success." Wilman's position as horticulturalist with Working for Wetlands is funded by the WWF Table Mountain Fund.
The Nursery Team at Rondevlei Nature Reserve
The next good rains in the Cape Peninsula will see a Working for Wetlands team traipsing out to rehabilitation sites on the Prinskasteel River to return the plant to its natural habitat.
Erica verticillata is one of about 80 fynbos wetland species propagated for replanting at Working for Wetlands rehabilitation sites. This year the Western Cape team propagated over 100,000 individual plants.
Victoria Wilman email
The Gumboot is a
monthly Newsletter produced by the Working for Wetlands programme and
dedicated to wetland news in South Africa.
Working for Wetlands is a government programme dedicated to the rehabilitation, protection and sustainable use of South Africa's wetlands. The programme is managed by the South African National Biodiversity Institute (SANBI) on behalf of the departments of Environmental Affairs and Tourism, Water Affairs and Forestry and Agriculture and forms part of governments Expanded Public Works Programme.