Australasian Science: Australia's authority on science since 1938

Perversity in the Pasture

By Don Driscoll and Jane Catford

Hundreds of the invasive plant species that inflict environmental and economic damage in Australia were originally developed and distributed as pasture species, yet we don’t seem to have learnt from these mistakes.

The full text of this article can be purchased from Informit.

African lovegrass was used to “improve” pasture in Australia for almost 100 years, but is now declared a weed in four Australian states and the ACT. It has been of little value in pastures, poses a substantial fire risk and threatens a range of native species. Similarly, gamba grass was widely promoted in northern Australia by the cattle industry and government. It is now listed as a weed of national significance.

Agricultural weeds cost Australia an estimated $4 billion every year, and the environmental damage is thought to be of a similar magnitude. Introducing these pasture species was a big mistake that Australians will continue to pay for indefinitely. We face increased fire risks, increased management and weed control costs, as well as ongoing loss of our natural heritage.

So we’ve learnt our lesson, right? Well, as incredible as it seems, we don’t seem to be learning at all. Agribusinesses still develop and promote new varieties of species that are known invasive weeds.

When we undertook a global survey of pasture plants we revealed that more than 90% of plant species developed and sold by agribusinesses are weeds somewhere in the world, and on average 30% are weeds in the country in which they are promoted. In Australia, species promoted by agribusiness include orchard grass, canary grass, tall fescue and sub clover. These species are all...

The full text of this article can be purchased from Informit.