Weeds and Bushcare News

Australia's Landscape 'Under Seige'

a timely Media Release from the Co-operative Research Centre
for Australian Weed Management

January 5, 2005

Australians touring their native land this holiday season may be seeing parts of it for the last time.

The native Australian bush, including many National Parks and nature reserves, is being slowly engulfed by an army of alien plants that are wiping out vast tracts of native landscape, along with their plants and animals.

"Few people seem to realise that the rate of landscape loss to introduced plants is accelerating," warns Dr Rachel McFadyen, Chief Executive Officer of the Co-operative Research Centre for Australian Weed Management.

"Already more than 27 million hectares have been swamped by over 2500 foreign invasive plants, and new threats are emerging constantly as plant imports continue to rise.

"Besides the damage to native landscapes, weeds inflict a $4-5 billion loss on the economy, mainly through agriculture, and a growing toll of ill-health among people who suffer allergies, lung problems or poisoning," she says.

Paying for the harm done

"One way to look at this is that it takes almost the entire earnings of the gold industry just to pay for the harm done to our economy by weeds. And that takes no account of the harm done to the environment."

Dr McFadyen says that Australians are failing to recognise the scale of the current exotic plants menace to the continent.

"Salinity has so far devoured 2.2 million hectares (m ha) of the landscape, and we recognise that as a real problem – whereas weeds dominate 27 million hectares and people hardly seem aware."

Blackberry alone now infests about 8 m ha of Australia, while prickly acacia covers 6.6 m ha and lantana another 4 m ha.

Despite the scale and urgency of the problem, total spending by all governments on control of weeds in conservation areas is about $20 million a year - whereas the National Salinity Plan has a budget of $1.4 billion.

Those 'pretty plants' are often weeds

"As Australians take time off to look at their country over the break, I'd urge everyone to try to be more aware of what they're looking at.

"The 'pretty plants' you see are often weeds, introduced for aesthetic reasons, but now playing havoc with our landscape.

"Take action by talking to politicians at every level – local, state and federal – and encouraging them to take further action on this immense problem.

"And become educated about what you plant in your own garden, remembering that it can escape into the landscape and contribute to its destruction."

Dr McFadyen says that in the last 200 years Australia has imported some 28,000 species of plants – compared with the 25,000 native species already here – and the rate is increasing, as more and more exotics come in.

On past experience, about one in every ten imported plants will become naturalized here and of these, one or two will become a serious weed.

Always another new weed ...

"Plants like bridal creeper or rubber vine can completely smother the landscape and eliminate all native plants and animals. Fortunately we are now having some success in controlling these with an introduced fungus – but with the rate of imports there is always another new weed waiting to establish itself."

Dr McFadyen says Australia has demonstrated several times in the past century that it is possible to control a major weed – but it requires both willpower and sufficient resources to do so successfully.

She says there is a need for a national strategy for dealing with exotic plants:

  • a co-ordinated approach to rapid detection and eradication (or containment) of new plant invasions
  • improved management of existing weeds using biocontrol and integrated control tactics
  • an additional $20m a year to deal with new invaders before they become a real menace
  • a more selective approach to keeping weeds out of Australia

"It's high time Australians woke up to weeds. They are not some minor nuisance in our backyards. They are wholesale destroyers of our countryside, our health and our prosperity."

More information:

Dr Rachel McFadyen, Weeds CRC, 07 3362 9388 or 0409 263 817
Peter Martin, Weeds CRC, 08 8303 6693 or 0429 830 366

Photographs available:
Sally Vidler, Weeds CRC, 08 8303 7209 or 0419 184 153
sally.vidler@adelaide.edu.au
www.weeds.crc.org.au