The Bouchard Finlayson biological control reserve

A note from Professor Cliff Moran (research area):

In the context of conservation, internationally, it is important to appreciate the uniqueness, value and scientific significance of the Cape Floral Kingdom (CFK). It is one of only six floral Kingdoms worldwide and it is the only one contained in a single country. Twenty-three percent (just over 9000 species) of Africa’s plant diversity is contained in a strip of land from Namaqualand to Port Elizabeth, which makes up only 0,3 percent of the land area of the entire African continent. About 7700 of the plant species in the CFK are classified as ‘fynbos’ plants, a vegetation type of quite extraordinary richness, beauty and diversity.

Invasive alien plants such as the tree species Hakea, Eucalypts and Acacias (originally imported from Australia), and Pine trees (from Europe and North America) as well as other alien species, are a serious problem in South Africa because they displace the fynbos vegetation, use large amounts of water, pose an increased fire hazard because the resultant fires are extremely hot, destroying the native vegetation and leading to soil erosion. Seed banks from the invasive trees build up in the soil over many years and when a fire occurs, the seeds germinate causing an ongoing and vicious cycle of re-growth.

The problem of alien invasive trees can be partly combated by herbicidal and mechanical clearing but these methods are expensive and never-ending. The only other viable and sustainable option is to use biological controls, i.e. the use of plant-feeding insects and diseases that are imported from the countries of origin of the alien invasive trees and that have been rigorously tested for safety – they will only feed on the species of tree that has been targeted for biological control. Seed-feeding insects are of particular value in curbing the invasiveness of many of the alien tree species.

The value of ecosystem services (water, grazing, biodiversity, eco-tourism, and the cut-flower and thatching trade) generated from the fynbos has been calculated to be worth about £2 billion annually and cumulative yearly savings from biological controls are about 14%. Careful analyses have shown the extraordinary economic benefits of biological control with benefit: cost ratios calculated at unprecedented levels of 100s: 1.

An area of alien vegetation at the Bouchard Finlayson estate in the Hemel en Aarde Valley, near Hermanus, has been especially dedicated for more than fifteen years to research on biological control. The Bouchard Finlayson biological control reserve is an experimental site where observations on biological control can be conducted, and crucially, it is one of the main ‘nursery’ sites where the insects that are used for biological control can be allowed to multiple and serve as a source of ‘inoculums’ for distribution to other areas in the country infested with invasive trees and in need of biological controls.

In this context it is a pleasure to acknowledge the sustained support of the Bouchard Finlayson Wine Estate and particularly, Mr. Peter Finlayson. Mr. Finlayson and conservationist Mr. Frank Woodvine are thanked for their efforts, understanding and foresight, in allowing the maintenance of the Bouchard Finlayson biological control reserve on behalf of researchers and scientists, and in the greater interests of conservation of the unique and special fynbos biome.

Just for the record: I have worked as a research scientist in the field of biological control for over 40 years. I served as Dean of the Faculty of Science at the University of Cape Town for 13 years and am currently involved with the University as a researcher and, more widely, as a consultant. I have published in excess of 100 research papers in scientific Journals of high international repute.

Dr V C Moran Professor Emeritus University of Cape Town