C·I·B workshop on the status of river red gum in South Africa

The Centre for Invasion Biology (C·I·B) hosted a workshop titled “Eucalyptus camaldulensis in South Africa: assessing its past, present and future” on 16 March 2018 at the Stellenbosch University’s Botanical Garden.

The workshop focussed on the river red gum tree (Eucalyptus camaldulensis) which is the gum tree species with the greatest distribution and impact as an invader in South Africa. The species has been widely planted for commercial and non-commercial use in many parts of the country since its introduction in 1870. Planted and invasive stands of the tree are conspicuous features in many South African landscapes. However, little is known about the river red gum in South Africa — for example, how it spreads from planting sites, how invasive populations impact native biodiversity, which of the species’ genotypes are represented in planted and invasive populations, and how people perceive the costs and benefits of the species in different contexts.

The workshop was a first step towards a comprehensive review of what is known about river red gum in South Africa and an assessment of what information is needed to provide guidelines for sustainable management of the species. To this end, a diverse team of researchers and management experts from the following institutions came together to discuss what we know about river red gum in South Africa: Agricultural Research Council (ARC), Council for Scientific and Industrial Research (CSIR), Forestry and Agricultural Biotechnology Institute (FABI, University of Pretoria), Forestwood cc, Institute for Commercial Forestry Research (ICFR, University of KwaZulu-Natal), Invader Plant Specialist (Pty) Ltd, South African National Biodiversity Institute (SANBI), Sappi Forests, the Centre for Invasion Biology (C·I·B), Stellenbosch University’s Department of Conservation Ecology and Entomology, University of Venda’s Department of Ecology and Resource Management, and Working for Wetlands (Department of Environmental Affairs). The team discussed and compiled information on the species’ introduction and planting history, current distribution in South Africa, its value for commercial forestry, impacts as invader, associated pests and pathogens, people’s perception of the species and conflicts of interest, management and restoration options, knowledge gaps and further research needs.

The information compiled during the workshop will feed into a comprehensive species profile on river red gum in South Africa which will be published in an international peer-reviewed journal. This kind of species profile could potentially serve as a model for the types of information that are needed for developing objective management strategies for non-native tree species in different parts of the world. Moreover, the workshop motivated the formulation of further research ideas on the subject which will result in future publications and provided a valuable platform to initiate inter-disciplinary research collaborations.

The C·I·B funded workshop was organized by C·I·B Postdoctoral Fellow Heidi Hirsch, with help from the C·I·B Director Dave Richardson.

People who are interested in aspects of river red gum in South Africa are encouraged to contact Dr Heidi Hirsch (

Participants at the workshop

Participants at the workshop on the river red gum (Eucalyptus camaldulensis) which was held at Stellenbosch University’s Botanical Garden on 16 March 2018. Back row, right to left: Sheunesu Ruwanza (Dep. of Ecology & Resource Management, University of Venda), Michael Cheek (SANBI), Jaco Le Roux (C·I·B), Graham Harding (Invader Plant Specialist (Pty) Ltd), Mark Gush (CSIR), Hildegard Klein (ARC), Heidi Hirsch (C·I·B), Pieter Winter (SANBI), Coert Geldenhuys (Forestwood cc), Sebinasi Dzikiti (CSIR), Dave Richardson (C·I·B), Andrew Morris (ICFR), Brett Hurley (FABI, University of Pretoria), Francois Roets (Dep. of Conservation Ecology & Entomology, Stellenbosch University). Front row, right to left: Christy Momberg (C·I·B; scribe), Wayne Jones (Sappi Forests), Farai Tererai (Working for Wetlands, Dep. of Environmental Affairs), David Le Maitre (CSIR). (Photo: Suzaan Kritzinger-Klopper)