The common Pig Face (Carpobrotus rossii), often listed as a weed in areas is a good example. The foliage of this common species can be used add salt content in roasts, and the extremely sweet berries when ripe can be used as a natural sweetener or eaten by there selves. Pig face is found all along the eastern coast of Australia. In a survival situation, the succulent foliage is a vital source of fresh water, in often salt ridden environments.
Another vital example of a native food substitute is several species of the family Prostanthera. Prostanthera ovalifolia, commonly known as the mintbush is indigenous to the east coast of Australia. It is easily identifiable by its strong mint smell and oval like foliage, as well as stunning mauve purple flowers. the foliage makes absolutely terrific jam and preserves, and is also an able substitute for mint in recipes.
Native's can also substitute for common vegetables, the rhizome of the native mat-rush (Lomandra longifolia) when cooked tastes precisely like asparagus and is extremely rich in nutrients. The seeds can be ground and used as a flour substitute.
These three species are just the tip of the iceberg though, with there literally being thousands of eatable Australian species, with applications in modern kitchen outside of survival uses. Most of these plants are incredibly tolerant of poor soils and most are drought tolerant. A future plan of mine is to create a garden purely consisting of indigenous eatable species, harvest able all year round.
It is important to consult a reputable source before trying any source of bush tucker though, with many species poisonous to humans.
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