Australia’s unique landscape is both beautiful and challenging, with many regions facing the constant threat of bushfires. This is why vegetation selection is important for planting in bushfire prone areas. Many native trees are adapted to the local climate, resistant to fire, and have characteristics that help them survive or recover after bushfires they can not only enhance the beauty of outdoor spaces but can provide a buffer against the ever-present risk of bushfires. The varying characteristics of our Australian native trees allow them to survive and often thrive, providing many ecological benefits to the surrounding area.
What is Flammability
All vegetation will burn however different plants have different levels of heat that are required to set them alight. This is called the flammability of a plant and not all vegetation has the same flammability. What is flammability you ask? The following points by the Country Fire Authority (VIC) offer an overall guide on how to determine the flammability of plants.
Plant flammability is described as a combination of:
- the time taken for a plant to ignite
- how readily it burns when the ignition source is removed
- how much material there is to burn
- how long it takes for all available fuel to be consumed
Flammability will vary depending on:
- a plant’s age, health, physical structure, and chemical content
- the daily and seasonal climatic variations
- location of the plant in relation to other vegetation and flammable objects
- the specific part of a plant – some parts of plants are also more flammable than others.
This means that by selecting the right trees for your space you can reduce the potential risk of fire to your property and buildings.
Fire-resistant or Fire-retardant Species
Here’s a diverse list of native Australian tree species that are known for their fire-resistant or fire-retardant qualities:
- Grevillea species : Grevilleas are known for their unique and colourful flowers. They are generally adaptable to a variety of conditions including fire-prone environments. Eg. Grevillea robusta or Silky Oak
- Banksia species : Banksias are known for their thick, leathery leaves and unique flowers which have fire-resistant seed pods that open after a fire, allowing for the release of seeds. They are generally well adapted to fire-prone areas. Eg. Banksia integrifolia or Coastal Banksia
- Brachychiton species : A deciduous tree with lobed leaves and striking floral displays they are well-suited to hot and dry conditions. Although they are not strictly fire-resistant, they can recover from fire through regrowth from the base. Eg. Brachychiton acerifolius or Flame Kurrajong
- Acacia species : Acacias are diverse and widespread in Australia. Many species are fire-retardant and can resprout and regenerate after a fire. Eg. Acacia fimbriata or Brisbane Wattle
- Acmena or Syzigium species (Lilly Pilly species) : Dense rainforest species that are fire-retardant and will resprout from the trunk after a fire. Eg. Acmena smithii or Lilly Pilly
How to Select Plants in Bushfire Areas
When selecting trees for fire-prone areas it is best to opt for trees with characteristics such as low flammability, thick bark, lignotubers, or the ability to resprout, which enhances their resilience to fire. Some further considerations in designing for a more fire-resistant landscape are:
- Strategic Planting: Strategically choosing the location and spacing of trees to allow for adequate distances between fuel sources can allow for more defensible zones and help reduce the spread of fires. Remember to keep in mind factors like slope and wind direction.
- Mulching: Use organic mulch around trees to retain soil moisture, suppress weed growth and create a protective layer across planting areas whilst allowing for a fire-resistant buffer.
- Regular Maintenance: Keep your landscape well-maintained by removing any dead or dry vegetation, including branches or leaf litter, reducing the accumulation of fuel for potential fires.
- Water Management: Adequate watering, especially during dry periods, can improve the health and resilience of trees which helps them withstand the stress of fire.
A fire-resistant landscape doesn’t mean sacrificing the beauty and shade that trees bring to your outdoor space. By selecting native Australian trees with fire-adaptive characteristics, you can create a landscape that withstands the heat and contributes to the safety and resilience of the community. Planting in bushfire areas means choosing wisely, plant strategically, and enjoy the benefits of a landscape that coexists harmoniously with Australia’s challenging conditions. It’s crucial to consult with local landscape architects or horticulturists familiar with the specific conditions of your area for personalized advice on plant selection and outdoor design. If you would like more information on designing outdoor spaces in fire-prone areas, please contact us today about your project.