Eucalyptus camaldulensis in South Africa – past, present, future

Abstract

Eucalyptus camaldulensis can be seen as an iconic tree of superlatives. It is the eucalypt with the widest native range, and one of the most widely planted eucalypts around the globe. In South Africa, it is the most widespread and the most aggressively invasive eucalypt. It has many uses, but also causes major impacts. However, little is known about key aspects of its ecology in South Africa, including its invasion history, invasion processes and dynamics, and people’s perceptions of its positive and negative effects on ecosystems. Such knowledge is crucial for developing robust and defendable guidelines for sustainable management of the species. This paper provides a comprehensive dossier of the species in South Africa. It reviews what is known of its introduction and planting history, its current distribution, its value for commercial forestry and other uses, its impacts as an invasive species, pests and pathogens associated with the species, people’s perceptions of the species and conflicts of interest, and the options for management and restoration. The review reveals that E. camaldulensis is a tree of many contradictions in South Africa, making it a poster-child example of a conflict-generating non-native species. Based on available knowledge, we assess options for improved management. We highlight several knowledge gaps which need to be addressed in more detail through future research. It is hoped that this species profile will 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.

Keywords:

• Conflicts of interest
• Eucalyptus
• impacts
• introduction history
• invasive species management
• pests and diseases
• tree invasions

ACKNOWLEDGEMENTS

This paper emerged from a workshop held on 16 March 2018 in Stellenbosch that was coordinated and funded by the DST-NRF Centre of Excellence for Invasion Biology (CIB). Besides the authors of the paper, we thank all workshop participants as well as Mark Anderson (BirdLife South Africa), Felicity Blakeway (Council for Scientific and Industrial Research), Trevor Booth (CSIRO Land and Water, Australia), Andre Botha (Endangered Wildlife Trust), Brian Bredenkamp (Department of Forest and Wood Science, Stellenbosch University, retired), Val Charlton (LANDWORKS), Richard Dean (FitzPatrick Institute of African Ornithology, University of Cape Town), Ben du Toit (Department of Forest and Wood Science, Stellenbosch University), Peter Dye (Restoration and Conservation Biology Research Group, University of the Witwatersrand, retired), Andrew Jenkins (AVISENSE Consulting), Leandra Knoetze (Unit for Environmental Sciences and Management, North West University), Johan Pauw (South African Environmental Observation Network), Ross Shackleton (University of Lausanne, Switzerland), Joel Syphus (Kluitjieskraal Nursery, retired) and Andrew Wannenburgh (Department of Environmental Affairs), as well as Sabrina Kumschick and Khensani Nkuna (CIB and South African National Biodiveristy Insitute) for sharing information and perspectives.

DISCLOSURE STATEMENT

The authors declare that they have no competing interests.

SUPPLEMENTAL DATA

Supplemental data for this article can be accessed here https://doi.org/10.1080/0035919X.2019.1669732

ORCID

Heidi Hirsch http://orcid.org/0000-0001-6506-5655

Susan Canavan http://orcid.org/0000-0002-7972-7928

Michael Cheek http://orcid.org/0000-0002-2244-3633

Sjirk Geerts http://orcid.org/0000-0003-0149-2783

Coert J. Geldenhuys http://orcid.org/0000-0003-3593-5247

Brett P. Hurley http://orcid.org/0000-0002-8702-5547

Jan-Hendrik Keet http://orcid.org/0000-0003-2610-9410

Hildegard Klein http://orcid.org/0000-0003-0584-7529

Sheunesu Ruwanza http://orcid.org/0000-0002-4731-0394

Brian W. van Wilgen http://orcid.org/0000-0002-1536-7521

Michael J. Wingfield http://orcid.org/0000-0001-9346-2009

David M. Richardson http://orcid.org/0000-0001-9574-8297

Additional information

Funding

This study was funded by the DST-NRF Centre of Excellence for Invasion Biology, Stellenbosch University, and the National Research Foundation of South Africa [Grant Number 85417 to DMR and 109467 to BWvW].