Photo: Fuel reduction burn in progress.
Forestry Tasmania undertakes planned burns for two main reasons: to improve the safety of the community by reducing fuel loads in production forests and other identified high priority areas, and to regenerate harvested forests in a similar manner to natural regeneration following bushfire. We plan and conduct our burns based on evaluation of weather and site conditions to optimise smoke dispersion away from population centres.
Fuel reduction burns
Fuel reduction burns are generally carried out in spring and autumn to take advantage of optimal weather conditions.
Fuel reduction burns are used to:
- protect communities and assets from bushfie
- maintain the health of fire-dependent vegetation communities
Smoke from fuel reduction burns typically remains near the ground and can cause pollution, so wind conditions and direction must be right before a fuel reduction burn can be carried out. Weather conditions must also be right: not too hot, not too dry or wet and ideally with a light wind blowing smoke away from any local communities.
For more information, see Fact Sheet No. 4 Bushfire management.
Tall wet eucalypt forests are most successfully regenerated if there is a major event that replaces the whole stand of trees leaving an exposed mineral earth layer. This allows new seedlings to germinate. In nature this is produced by bushfire. Over the past 20 years scientists have researched ways to produce these conditions but no acceptable alternative to clearing and burning has been found.
Regeneration burns are undertaken in a way that creates an intense convection current to take the smoke produced into the upper atmosphere and away from local communities at ground level. They are typically done in autumn.
Regeneration burns are used:
- to regrow harvested wet eucalypt forests, by reducing fuel levels and creating a nutrient-rich seedbed for seed germination (mimicking natural conditions)
- for site preparation as part of plantation establishment, to reduce fuel levels and increase planting space
While the smoke columns from these burns can sometimes be very visible from local communities, they rarely cause pollution at ground level.
A signifiant amount of planning is undertaken to try to ensure conditions on site as well as weather conditions are suitable to achieve an effctive regeneration burn.
For more information, see Fact Sheet No. 7 Regeneration burns.
Coordinated Smoke Management Strategy
Forestry Tasmania has been instrumental in improving smoke management in Tasmania. This has led to the development of the Coordinated Smoke Management System now in place across the State.
This program, which was developed with the Environmental Protection Authority and is run by the Forest Practices Authority, sets a maximum amount of smoke that can be released each day into 11 defined Tasmanian ‘airsheds’.
Key principles of the Coordinated Smoke Management Strategy include:
- planning for burns to take place when forecast weather conditions indicate the smoke will be dispersed away from communities
- minimising or not conducting burns on days when poor smoke dispersion is likely
- not conducting burns that may affect significant public events
Currently the Coordinated Smoke Management Strategy only applies to burns carried out by the forest industry and the Tasmanian Parks and Wildlife Service. Other agencies and private landowners who also conduct burns, do so outside of these arrangements.
We apply the principles above to all of our planned burns.
For more information, see Fact Sheet No. 14 Smoke management.