Australia is the world’s driest inhabited continent with 70% of its landmass being deserts or semi-deserts. It is a harsh country for plants to live – it is extremely dry and it gets periods of drought that can last for years. It is extremely hot, with temperatures in 50s (°C) during the summer so if it does rain, evaporation is quick. The soils are ancient, rich in salt and extremely infertile. How can plants handle all this, and what plants are found in Australian deserts?
Trees and Shrubs Some of the trees found in Australian deserts are the beautiful Ghost Gum (Corymbia sp.) which is almost iconic with its smooth silvery white bark; Mulga (Acacia aneura), Sandalwood (Santalum spicatum); Northern Cypress Pine (Callitris glaucophylla); Sandhill Wattle (Acacia ligulata); and Western Myall (Acacia papyrocarpa). Some of the shrubs found in Australian deserts are Narrow-leafed Hop Bush (Dodonaea viscosa), Emu Bush (Eremophila glabra), Low Bluebush (Maireana artstrotricha), Bladder Saltbush (Atriplex vesicaria) and Bullock Bush (Alectryon oleifolium).
Grasses and Desert Wildflowers The grasses that cover Australian deserts are hummock grasses, commonly known as Spinifex Grass. In semi-deserts, Mitchell Grasses are more common. Some of Australian many desert wildflowers are Sturt’s Desert Rose, (Gossypium sturtianum) Native Buttercup; the famous Kangaroo Paw (Anigozanthos sp.) and Sturt’s Desert Pea (Swainsona formosa) which can flower for weeks when it’s raining, then it just closes up and waits for more rain.
Australian Desert Plants Adaptations We usually think of a desert as a hot place. But that’s not what defines a desert. Australian deserts are hot, but there are also cold deserts in other parts of the world. What defines a desert is the amount of rainfall, which is extremely low. In Australian deserts, the rainfall is extremely unpredictable, so the plants have to have adaptations that allow them to survive without water for an unpredictable time. Different plants have different adaptations.
Courtesy of Tourism Northern Territory
Australian Desert Plants: Drought Avoiders Some Australian desert plants simply avoid the drought: when the rains come along, they sprout out, quickly reproduce and die just weeks later. Their seeds are covered in chemicals that don’t let them germinate. When the rains come along, that chemical is washed away and the plants start growing.
Courtesy of Tourism Queensland
Drought Resisters: Adaptations to Consume a Lot of Water Drought Resisters are plants that have adaptations that allow them to live through the periods of drought. Many Australian desert plants such as trees and scrubs have either a very deep root system that reaches to the groundwater, or a very spread-out root system which extend far beyond the tree canopy and lie just below the surface. These extensive root systems can capture a lot of water once the rains come along.
Drought Resisters: Adaptations to Store a Lot of Water It’s not only about getting the water, it’s also about storing the water. Plants that conserve water in their leaves, fruit, stems or roots are called succulents. Because water escapes through leaf surfaces, a common adaption is to reduce that surface. Many desert plants have small spiny leaves, often long and slender. Some have glossy leaves to reflect the sun’s heat, others have waxy leaves to prevent the water from escaping. Yet others have powdery surfaces, or surfaces covered in small hair. Some plants also have behavioural adaptations – they can turn their leaves edge-on towards the sun, or only open their pores during the night when it’s cooler and evaporation rates are lower. Some desert plants are nearly leafless, some curl their leaves and some drop their leaves during the dry periods.
NOTE: This website is written in British English, which is the English we use in Australia. You will find words like "traveller", "harbour" and "realise", and they are all correct in the language used in Australia.
