DISEASE (DIEBACK) MANAGEMENT
What is Dieback?
Dieback is a water mould (Phytophthora cinnamomi). It is one of the most common and damaging plant diseases in Western Australia, with over 2300 native species at risk (1). It is a highly destructive plant disease that can impact entire ecosystems, biodiversity, cultural values and have significant financial implications for industries, government and landowners attempting to mitigate the disease (2).
1. Dieback Working Group. Dieback [document on the Internet]. Dieback Working Group; 2018. Available from: https://www.dwg.org.au/publications-links/publications/download-info/dwg-flyer
2. . Dieback Working Group. Phytophthora Dieback[document on the Internet]. Dieback Working Group; 2019. Available from: https://www.dwg.org.au/about-dieback/phytophthora-dieback/
What areas of Perth are affected by Dieback?
Phytophthora cinnamomi has spread across a large range of the south-west of Western Australia (Figure 1). For detailed information about affected areas in the Perth Metro Area go to the Dieback Public Map.
Figure 1: Extent of Phytophthoracinnamomiin Western Australia (Source: Department of Biodiversity, Conservation and Attractions, 2017).
How does Dieback affect bushland in the Perth Metro Area?
Infection by this water mould is a major threatening process throughout Western Australia, but of particular importance for management in Perth due to the small and isolated character of local reserves within the metropolitan area. The presence of dieback can severely reduce canopy and ground cover as well as species composition, affecting the conservation character of the site.
Symptoms of the disease are not easy to detect as the plants often appear to be dying from drought. However, symptoms include yellowing leaves and thinning of the crown, eventually resulting in tree death (1).
1. Australian Capital Territory Government. Symptoms of dieback [document on the Internet]. ACT Government; 2018. Available from:https://www.environment.act.gov.au/act-nrm/investment-plan/biodiversity-overview/climate-change-building-landscape-resilience/dieback/symptoms-of-dieback
What causes Dieback to spread in the Perth Metropolitan Area?
Walking through bush reserves, or recreational activities such as off-road 4WD driving and BMX bike riding increase the spread of the disease. Management focuses on reducing the human footprint in local reserves, and educating the community about steps they can take to minimise the risk of introducing dieback into their local reserve. Boot-cleaning stations at the entrance to paths are increasingly being used in local parks and conservation areas.
Is Dieback the only disease that affects biodiversity in Perth?
No, many plant pathogens occur naturally in Western Australia, and others are introduced. Some other pathogens that affect biodiversity in Perth include, but are not limited to Uromycladiumtepperianum (rusts), Pucciniapsidii (Myrtle rust), Armillaria luteobubalina (Honey Fungus), Canker disease, Mundulla Yellows, and Sphaeropsissapinea (Sphaeropsis blight). For further information on these diseases check out the Department of Primary Industries and Regional Developments Native Plant Diseases.
Which native plants are susceptible to Dieback?
Phytophthora cinnamomi affects more than 40% of all native plant species. The Centre for Phytophthora Science and Management (CPSM) have created a list of Western Australian Natives Susceptible to Phytophthora cinnamomi. Additionally CPSM have also produced a list of Western Australian Natives Resistant to Phytophthora cinnamomi.
Dieback can also be an issue in nurseries and gardens. For information on native garden plants that are resistant to dieback click here. For information about how to manage dieback in nurseries click here.
WHO MANAGES DISEASE IN WESTERN AUSTRALIA?
Private Land Owners / Individuals
Individuals and community members play an important role in managing the spread of dieback. Check out the links below for steps that can be taken to reduce the spread of dieback in reserves and on your property.
- Dieback Hygiene Guidelines
- How to clean your vehicle to prevent the spread of Phytophthora Dieback
- Managing Phytophthora Dieback on Your Block and in Bushland
- LoanPhosphiteTreatment Equipment for Private Property
Community Groups / Land Managers
The Dieback Working Group have excellent resources on management options for land carers, local councils and managers. These resources include the ManagingPhytopthoraDieback Guidelines 2000and Managing Phytophthora Dieback in Bushland.
Further resources for community groups and managers include information on dieback treatments such as Dieback Sprayingand LoaningPhosphiteTreatment Equipment for Common Reservesand Dieback Stem Injectionby the City of Kalamunda and the Dieback Working Group.
Local Government Authorities (LGA’s) manage many bushland reserves with high conservation values so implementation of effective dieback management procedures is critical to the long-term sustainability of these areas. Councils across Perth have created Disease and Dieback Guidelines for their local reserves. These are listed below.
Department of Biodiversity, Conservation and Attractions (Department of Parks and Wildlife)
The State Government is responsible for the management and protection of forests in Western Australia. The Department plays an active role in research, while also implementing programs to detect and diagnose dieback on areas managed by The Department of Parks and Wildlife. The Department offers a Vegetation Health Service, where identification and detection of Phytophthoraspecies can occur for samples from conservation estates, timber harvesting, as well as mining, industry and research areas.