Phytophthora Dieback

1. Phytophthora Dieback The biological bulldozer Adapted from presentations by Dr Chris Dunne, Science Division, DEC

2. Threats to rare flora of the south-west of WA Consequences of construction developments i.e. road works, recreation Invasive weeds Grazing by feral/ introduced animals Salinity, water table change Small/declining populations Demographic /genetic effects Mining activities Drought/climate change Land clearing Phytophthora dieback

3. What is Phytophthora dieback? • Caused by a water mould called Phytophthora cinnamomi • Phytophthora is Greek for ‘plant destroyer’ • organism was first identified on the roots of a cinnamon tree • P. cinnamomi feeds off plant roots • Causes root rot which stops plant taking up nutrients and water

4. A brief history Quarantine Infested gravel used for roadmaking Introduction of European plant species 1829 1989 1920 1948 1964 1996 1973 Research station est. Dwellingup Pc identified as causal agent First recorded unexplained tree deaths (Karragullen) Early European settlers arrive Use of phosphite

5. Lifecycle of P. cinnamomi

6. >800mm pH 5-6 Ideal environment 20oC-30oC • Therefore: • Forested areas with higher rainfall • Grows and spreads best in autumn and spring

7. Where is dieback found? bushland gardens nurseries horticultural plantations

8. Impact on native flora • Of 5710 recorded species of plant: • 2300 (40%) susceptible to Phytophthoradieback • 800 (14%) highly susceptible to Phytophthoradieback

9. Jarrah forest – Dwellingup

10. Banksia woodland

11. Stirling Range National Park

12. South Coast

13. Impact Impact on animals? • Loss of: • food • habitat • shelter

14. Distribution of Phytophthora cinnamomi

15. P. cinnamomi in Western Australia

17. Perth Scarp

18. How is it spread? 4WD Hiking boots Road making Trail/mountain bikes Animals Irrigation Infected plant material

19. Management of Phytophthora dieback • Interpretation and mapping • Is Phytophthora dieback known or likely to be in an area, or at your site? Do you need more information? • Identify priority areas, species or communities for protection • Declared rare flora • Endangered fauna • Is the area protectable • Prevent accidental introduction • Minimise spread • Reduce impact

20. Dieback Interpretation & Mapping • Dead “indicator plants” • Structural change • Chronology of deaths • Soil/tissue sampling

21. Indicator species Banksia grandis (Bull Banksia) Patersonia spp. (Flag Flower) Xanthorrhoea preissii (Balga)

22. Field Detection Rich proteaceous shrubland Direction of travel Disease Front Depauperate sedgeland

23. Identify protectable areas • Focus resources on areas of highest biodiversity value • Declared rare fauna • Endangered fauna • Threatened ecological communities • Focus resources on areas which can be protected • Uphill from known infections • Large enough to protect (>2ha) • Able to be effectively quarantined (limited public access, sources of infection can be mitigated or removed) • Focus resources on areas where the benefits of hygiene will last more than a few decades

24. Prevent accidental introduction • Readily introduced in infested material (e.g. soil on footwear or vehicles, infected plant material, gravel for road construction, nursery stock) • Impossible to eradicate • Prevent introduction by • Use of certified dieback free materials • Remove and control access • Hygiene – footbaths and vehicle washdown

25. Remove and control access X X X X CLEAN ON ENTRY POINT

26. Remove access Control access

27. Hygiene Footwear & equipment Vehicles

28. Minimise spread Reduce water flow Barriers to infection

29. Reduce impact - conservation Seedbank Revegetation Translocation

30. Phosphite • Highly effective – gives short term resistance to some plants • Low toxicity • Environmentally friendly • Can be sprayed or injected

31. What can you do?