Dieback, or more correctly Phytophthora
Dieback, is a deadly plant disease that devastates our forests, woodlands
and heathlands. The disease is caused by the introduced pathogen Phytophthora
cinnamomi. Phytophthora dieback is causing significant damage in the south-west
of Western Australia because:
- Over 40% (2300) of native plant
species in the region are susceptible (Shearer et al., 2004)
- The climate and soils of the south-west
region suit its survival and spread, and
- it was spread widely before it
was identified as the cause of permanent damage to our ecosystems.
Phytophthora dieback spends its entire
life in the soil and in plant tissue. It attacks the roots of plants and
causes them to rot. This kills the plant by limiting or stopping the uptake
of water and nutrients. The pathogen is able to survive within plant roots
during the dry soil conditions commonly experienced during the summer months.
In sloping areas Phytophthora dieback spreads quickly when its microscopic
spores move downwards in surface and sub-surface water flows. It spreads
slower up-slope and on flat ground (approximately one metre per year) because
it is restricted to movement by root-to-root contact.
Responsible bushwalkers take steps to
ensure they do not contribute to the spread of the pathogen. Minimise the
risk of spreading the dieback pathogen in dieback affected areas by:
- Keeping to tracks, and avoiding
muddy areas and puddles.
- Making sure footwear is free of
mud and soil when arriving at a bushwalking site, and trying to keep footwear
as clean as possible during the walk.
- Using footpaths or shoe cleaning
facilities when provided.
- Obeying 'track closed' signs on
walk tracks.
- Making sure your vehicle is clean
when arriving at bushwalking sites, and parking your car in designated
locations.
Bushwalkers may carry equipment in their
packs and/or vehicle to help keep their footwear clean. A 'bushwalking hygiene
kit' should contain a bag to collect scraped off soil/mud, large and small
brushes and a bottle of water (from mains supply). Methylated spirits can
be applied using a spray bottle to sterilise the soles of shoes.
(Adapted from the Dieback Working Group
- http://www.dwg.org.au/)
