THE SCIENCE OF LOW FLAMMABILITY PLANTINGS

Many decades of scientific testing have shown that while there is no such thing as a fireproof plant, some plant species burn less well than others.

Recently there has been renewed research into plant flammability, including in New Zealand.

A standard approach is to burn 70cm-long shoots (on a device called a ‘‘plant BBQ’’), which allows the testing of many species relatively quickly.

This approach has been validated against other methods, such as the expert opinion of fire managers.

HOW CAN I USE LOW FLAMMABILITY PLANTS TO PROTECT PROPERTY?

It is best to use exclusively low flammability planting in the priority safety zone of defensible space (0-10 metres) around your home and other structures.

Consider replacing any high flammability plants or trees in zone 2 (10-30m) around your home and structures with low flammability plants.

At a larger scale, you could consider planting green firebreaks – strips of lowflammability vegetation established at strategic locations across the landscape to reduce fire spread.

Green firebreaks have been widely used around the world and could be planted on the urban edge to help protect whole neighbourhoods.

They have been deployed around New Zealand, for instance in Wellington and Porirua, while Christchurch City Council has established green firebreaks following the Port Hills fires.

HOW DO I ESTABLISH LOW FLAMMABILITY PLANTINGS AROUND MY HOME?

Establishment of low flammability plantings should be planned months to a year in advance. First, identify which low flammability species are suitable for your area.

Key resources on this can be found at checkitsalright.nz.

Low flammability plants in New Zealand include native tree and shrub species such as Griselinia littoralis (kapuka, broadleaf), Pseudopanax arboreus (five-finger), Coprosma robusta (karamu), and Aristotelia serrata (makomako, wineberry).

For instance, planting a broadleaf hedge along your property could be a good way to help reduce fire spread.

Next, source these plants from a local nursery, realising you may need to order stock a year in advance. Ideally, use plants grown from local seed stock as these will be best suited to your local environment. Finally, plant them when soil moisture is at its highest, often May-August.

Remember it will be several years before certain plants are large enough to help protect your home from fire, and they need ongoing watering and maintenance, such as removal of any dead leaves and branches.

Low flammability plantings can help protect your home from fire but are best used as part of a wider range of fire prevention measures.

This article is published in association with Fire and Emergency NZ as part of a commercial arrangement between them and Stuff.