Old Man Saltbush (Atriplex nummularia) planted to protect areas that have a high risk of fire danger can be a useful strategy in times of need. There is no plant completely fire proof but there are some like saltbush which are much less likely to burn in the event of fire.

Old Man Saltbush plants have a number of out of the ordinary features that are advantageous during fire, some of these include:

1. Old Man Saltbush is an evergreen plant and does not lose its leaves all at once.

2. This saltbush is large enough in size to provide a physical barrier for an approaching fire. Plants have dense, leafy upright growth and this can provide an insulating barrier to radiant heat.

3. Old Man Saltbush has a high salt content throughout the entire plant including in the moist leaves. The salt and moisture retards the plant material from burning.

4. If many plants are arranged alongside one another in a hedge-like arrangement, they are able to act as a windbreak and slow dangerous winds when high fire conditions exist.

5. The dense plant material can act as an ember trap. Once embers are captured the salt content and moisture in the leaves retard fire flames.

During the 1800s and early 1900s the protecting qualities of Old Man Saltbush were recognised by many home gardeners. It was very fashionable and practical to establish an Old Man Saltbush hedge along the western “back fence” of rural homesteads for a few sensible reasons and one being fire protection. Such an Old Man Saltbush hedge is tough and hardy and once established it requires little additional water to grow well. The hedge physically sheltered the buildings and gardens from strong winds. If a fire should approach the Old Man Saltbush hedge its insulating effect protected the asset it sheltered.

We possibly need to reconsider the wisdom to our predecessors and reinstate the Old Man Saltbush hedge around buildings and other assets for its protection capability especially during fires.

The cultural requirements will dictate wether or not Old Man Saltbush is suitable to grow as a fire barrier in a particular area. The best conditions for Old Man Saltbush are.

1. High light conditions, full sunshine all year around is most desirable.

2. Alkaline soils. pH of at least six but the higher the pH reading the better. (Lime applications could be added to the soil to assist saltbush growth but this process does have limitations if pH is below 6.)

On a larger scale an Old Man Saltbush double row hedge permanently sited across a paddock perpendicular to the direction of the highest fire risk may also be a worth considering.

Each property or farm has many local factors affecting it when a fire strikes so there are too many possibilities to go into depth with design features in this document. As a general rule under ideal growing conditions for saltbush we would recommend the plants are spaced about one metre apart to bush together as a hedge. This spacing may be modified to 75 centimetres between plants in a garden situation if additional water is supplied. Spacing may even be widened to more than one metre if air flow between plants is more desirable.

Pruning or grazing the bushes annually is advisable to keep the leafy growth lush, attractive and healthy. Like most natives saltbush just loves a good chopping to avoid the development of trunks and woody growth at the expense of the more desirable leaf growth. Don’t be scared to hack it back!