Australia’s interior was once an entirely different scene to what we see there today, unbelievably, rainforests covered the land and dinosaurs grazed the lush, green vegetation. This prehistoric image for many Australians is very difficult to comprehend.

The world’s continents are continually in motion across the face of the planet. They travel at a rate we are not able to notice in a single human life time. The steady movement of the land masses in turn influences the ocean currents and water temperatures; this then affects the rainfall and air temperature over Australia. In the present day, the humidity and rainfall of central Australia are now very low and temperatures are extremely high.

During this remarkable climatic change the Australian plants also needed to make basic changes to their requirements from the environment. Many, many plant species did not make the necessary changes and are only found as fossils in the rocks.

The plant species that have successfully adapted or evolved in to these much harsher inland conditions are now the winners and they can be seen growing in these arid and semi-arid environments today. The saltbushes have come to flourish in the outback; they glisten quietly in the baking summer sun without any sign of distress. What an amazing journey through time for the good old saltbush, they have conquered climatic changes to thrive in these challenging ecosystems and not just merely to survive.

Old Man Saltbush, Atriplex nummularia, is one of the world’s most efficient plants in converting precious water and nutrients into valuable plant material Given the conditions it faces in the wild it is truly an amazing plant.

Old Man Saltbush in the wild near Balranald NSW

Two examples of these survival features of Old Man Saltbush are:

1. Leaf structure:

- Leaf colour is a silver-grey. This reflects excessive sunlight away from the plant like a mirror to reduce transpiration and water loss.

- Leaf size is not excessive to limit surface area which then limits the water loss from the plant.

- A wax-like covering on the leaf surface further restricts water loss.

- Leaves held mostly upright on the branches to avoid full exposure to the midday sun.

2. A massive and uniquely structured root system:

Old Man Saltbush grows naturally across the interior of Australia on varying soil types and environmental conditions. Once established, Old Man Saltbush is contented with scorching summer heat and high levels sunlight, in fact, the more it receives the better it grows. There are no dormant growth stages for saltbush during the seasons of the year this characteristic allows saltbush to be grazed at any stage during the year.

The introduction of sheep and cattle to inland Australia saw the saltbushes help produce legendary life stories of the outback. Sir Sydney Kidman of South Australia is one famous Australian who recognized the value in saltbush as a stock fodder plant.

“They passed through the mallee belt, then out on to plain country and were in the land of the sparse rainfall. The boy gazed upon a dull grey carpet stretching far away. He had never seen saltbush before. He felt strangely attracted to this little greyish bush; its somber colouring seemed typical of the area. This sweet, drought-resisting bush, with its mates the bluebush and cottonbush was destined to fatten millions of sheep and cattle for cities far away. And this boy’s destiny was to be linked with the saltbush.”

“Cattle King”; Ion Idriess; Angus & Robertson Publishers; 1936

The following quote may also indicate the high grazing performance of the original Old Man Saltbush stands –

“For producing the best qualities of beef mutton and wool, it has been proved that no other fodder plant or grasses equal the Saltbush, and bullocks fed upon the Murrumbidgee Saltbush flats, on Wagingoberembee Station near Narrandera, have realized the highest prices in the Melbourne market.”

A quotation from the Ag Gazette Vol. VIII 1897:-

Commercial sheep and cattle grazing pressures on the natural stands of Old Man Saltbush then intensified, more and more stock passed through the natural saltbush stands of inland Australia. Fences were built and set concentrated stocking occurred on the sought after saltbush stands. The cattle and sheep ate the more palatable plants over the less desirable ones; this placed an extra pressure on the original genetic diversity of the saltbush population, selective and over grazing began to take its toll, the quality and quantity of the natural saltbush stands began to decline.

It was the rabbit that struck the final and fatal blow to the Australian saltbush grazing business of the inland!

“But while the Cattle King planned and worked, while his army of cattlemen, drovers, office men, camp followers, with brain and hand and unswerving loyalty worked to his bidding, stock and vermin on lesser rainfall lands were eating him out. Eating all men out. Millions of hoofs trampling over the land, billions of claws rooting into the land, billions of teeth ceaselessly night and day eating deep into the roots of things.

The country might just have held its own had it not been for the rabbit plagues. They devoured not only the grass but the edible bushes. They destroyed the roots, the bulbs, the very source of life. In dry times they attacked the bush and shrub life in ravenous hordes, eating deep down to the last shreds. Then they started on the mulga-trees and leopard wood, eating the bark, ring-barking the tree life over huge areas, stripping the bark off the currant bushes. As time went on, clumps of dead timber reared dead limbs to a brazen sky. Nature provides for the continuity of tree life by sending up young trees. But these babies were rung and the bark eaten by ceaselessly gnawing teeth. Seeds of tree, shrub, and grasses were devoured literally in thousands of tons.”

“Cattle King”; Ion Idriess; Angus & Robertson Publishers; 1936

The Old Man Saltbush stands of inland Australia have never fully recovered from this rabbit pressure. Today we see only the bare remnants of these once tremendous stands of saltbushes. We can barely even imagine the livestock activity and business that once occurred in this very same land.

A remnant stand of wild Old Man Saltbush near Balranald, New South Wales.

Since the 1950’s South African researchers have been experimenting with Old Man Saltbush plants, breeding for greater palatability and increased fodder production. The South Africans identified Old Man Saltbush (Atriplex nummularia) as having the greatest commercial value for drought resistance and bulk fodder supply of all the saltbushes in Australia.

During the South African research they watched the stock, then selected the plants the stock preferred to graze, these plants were identified and left to set seed. New saltbush plantations were grown with the seed collected from the preferred plants and the watching and identification process was then repeated. The result of this methodology is a new improved Old Man Saltbush strain. It has been given the name “de Kock” Old Man Saltbush, after Gerhard de Kock, the plant breeder who had devoted his life’s work to drought-proofing South Africa. Leaves from this new Old Man Saltbush variety have been measured up to 75mm across compared to the original plants of about 2Omm.

At the present the best establishment of an Old Man Saltbush plantation is by planting the seedlings directly into the prepared site and caring for them until they are suitably established; direct seeding has far too many difficulties.

A grazing system with Old Man Saltbush has now been established and is recommended, it successfully mimics how it was grazed by wild herds for millennia in Australia’s outback. The key for its success in commercial saltbush plantations lies in the plants being grazed intensively for three months or less at a time, then being left to recover. This recovery period allows growth to recharge the plant’s energy reserves which in turn adds to the plantation’s longevity.