Forest dieback is one of the biggest threats facing our native bush, and human activity is responsible for its spread. Tools developed to contain and control dieback in Western Australia (WA) are now being used to combat it worldwide.

Phytophthora dieback is caused by the introduced plant pathogen Phytophthora cinnamomi (‘plant killer’ in Greek). It is a major threat to Australia’s native vegetation and dependent wildlife, as well as to many agricultural crops and garden plants. It has been recognised by the Commonwealth as a ‘key threatening process’ to Australia’s biodiversity.

It spreads through the movement of infected water and soil, especially by human activity.

More than 40 per cent of Western Australian native plants are susceptible to the disease (approximately 2,300 unique species), and over one million hectares is already infected in WA, particularly in the south west, one of the world's 35 biodiversity hotspots. Phytophthora dieback is also having a serious impact in other parts of Australia, and is of increasing concern in every continent except Antarctica.

Phytophthora dieback affects more than plants; is also a direct threat to native wildlife. Changing vegetation structure irrevocably alters the habitats that provide food and shelter for marsupials, birds, reptiles and insects.

Professor Giles Hardy
Phytophthora really is a ‘biological bulldozer’. You can be in Banksia woodland thick enough that you get scratched up pushing your way through. But once Phytophthora has been through, you can play a game of golf.
Professor Giles Hardy

The Murdoch Centre for Phytophthora Science and Management (CPSM) have developed strategies to limit the spread of Phytophthora since the early 1990s, with a particular focus on minimising its transmission by human activities. Their recommended quarantine, hygiene and work practices are now preventing the transport of infected soil and water across south-west Western Australia, and increasingly worldwide.

Working with major mining companies (e.g. Alcoa of Australia, Worsley Alumina, Iluka Resources and Tronox Ltd), CPSM's dieback management practices have changed mine planning and operating practice, giving companies access to areas they may not have otherwise been able to mine, improving their rehabilitation record, and helping maintain their social license to operate.

More generally, the CPSM has addressed many aspects of Phytophthora control and eradication, including reviewing the National Threat Abatement Plan for Dieback, and creating the ‘Review of best practice management for Phytophthora cinnamomi’, now cited internationally as a guideline to Phytophthora management.

Professor Giles Hardy, who leads CPSM, says 'the savings to industries across Australia runs into hundreds of millions of dollars, and preserving healthy ecosystems is priceless'.