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Scientists call for banning of dangerous grass in Northern Australia.

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Cooperative Research Centre for Australian Weed Management

MEDIA Release Phone 08 8303 6590 Fax 08 8303 7311

30 March 2008 EMBARGOED UNTIL Monday 31 March


Almost 200 ecologists and weed scientists have signed an open letter calling on the Queensland and Northern Territory Governments to ban the planting and sale of gamba grass (Andropogon gayanus), a dangerous exotic grass that fuels fires of such ferocity they could transform Australia's northern savannas into weed monocultures. The Gamba Declaration was launched in Brisbane today by Dr Rachel McFadyen, CEO of the Weeds CRC, and in Darwin by Professor Stephen Garnett, Director, School for Environmental Research, Charles Darwin University. "Future generations will ask how we could have been so stupid as to allow the planting of this grass. It's foxes and cane toads all over again, with the difference that we know full well what the consequences of gamba grass are," Dr McFadyen said. "It's a major threat to biodiversity, and it's a high fire risk for wildlife, humans and infrastructure." The African grass was assessed by officials in both WA and Queensland using a standard, national 'weed risk assessment' process developed by Australian scientists, Dr McFadyen said. "In both states this species failed the test miserably," she said. "WA then banned it, but Queensland has so far failed to act, presumably due to pressure from some pastoralists who favour it." Dr McFadyen said that the public needed to know that this grass is a first class weed that is very difficult to contain in fenced pastures. Once established in native woodland, the very hot fires it supports kill off the trees and eventually transform the landscape into a uniform African grassland. "For a large array of native plants, birds and animals, this spells the end of their ecosystem and habitat - they move out, or die," Dr McFadyen explained. According to Professor Garnett, the strong scientific support expressed publicly for the banning of this weed is unprecedented. "This simply reflects the overwhelming evidence that gamba grass is a truly high impact invader," Professor Garnett said. "We call such species 'ecosystem transformers', he said. 'It is highly irresponsible for us to continue planting such species when we know exactly what we are dealing with." "If it's not stopped it could infest vast areas of Northern Australia - up to 38 million hectares in the Northern Territory alone', he said. "The ban in Western Australia was the only sensible response," Dr McFadyen concluded. It's time now for Queensland and Northern Territory to do the same."

Contacts Dr McFadyen will be holding a press conference in Brisbane, on the front steps of Parliament House, 11 am, Monday 31 March. Professor Garnett will be holding a press conference at the School for Environmental Research, Charles Darwin University, Darwin, at 12 noon, Monday 31 March.

Interviews can be arranged by phoning Dr McFadyen in Brisbane on mob 0409 263 817, and in Darwin, Prof. Stephen Garnett on 08-8946 7115 or mob 0408 832 109 or Dr Stuart Blanch (WWF-Australia) on 0427 957 868. A copy of the letter with supporting information and quotes can be obtained from

Images High resolution weed photos can be downloaded directly from

THE GAMBA DECLARATION: Since gamba grass (Andropogon gayanus Kunth.) was introduced to Northern Australia from Africa in the 1930s as a pasture grass for cattle, it has spread to become one of Australia's worst environmental weeds. Gamba grass also threatens human health and safety, infrastructure and Indigenous cultural values. Growing up to 4 m tall in dense stands, gamba grass fuels dangerous fires, up to eight times hotter than natural fires, killing native savanna trees and grasses. As an ecosystem transformer, gamba grass reduces tree cover, changes water availability, depletes nutrients and increases greenhouse gas emissions. Under climate change, gamba-fuelled fires will become more frequent, which will increase greenhouse gas emissions. Gamba grass invasion is a serious risk to biodiversity, with several endangered and vulnerable species already being seriously affected. Unless banned and controlled it threatens to turn vast areas of Northern Australia's woodlands into gamba grass monocultures. It could infest 38 million hectares in the Northern Territory alone, if its current spread is not stopped. The Western Australia Government banned the sale and planting of the grass in January this year, and all known infestations in WA are to be eradicated. Accordingly, we call on the Queensland, Northern Territory and Federal Governments, as appropriate, to: " Urgently and totally ban the sale and planting of gamba grass in the Northern Territory and Queensland, and ensure this ban is properly enforced. " In Queensland, declare gamba grass a prohibited (Class 2) weed, and allocate sufficient resources to ensure its control with a view to eventual eradication. Where gamba grass has been planted, develop management protocols to prevent further spread. " In the Northern Territory, declare gamba grass a Class B/C weed, and allocate sufficient resources for early eradication of small and/or strategic infestations and control of larger infestations. Where gamba grass has been planted and is beyond eradication, develop protocols for the species' use to reduce threats to natural ecosystems and key ecological assets. " Carry out comprehensive mapping of gamba grass infestations in both Queensland and the Northern Territory, to better inform management decisions. " Develop and implement a well-funded, integrated plan of management to reduce and manage the threat of gamba grass across Northern Australia, such as through a Threat Abatement Plan under the federal Environment Protection and Biodiversity Conservation Act. " Determine the extent to which gamba-fuelled fires increase greenhouse gas emissions, and develop strategies to reduce those emissions. " Implement strategies to reduce the risks of gamba grass fires to human life and health, infrastructure and Indigenous cultural values

There is overwhelming scientific evidence, summarized in the Appendix to this letter, that gamba grass is a highly invasive and dangerous weed. This is reflected in the results of Weed Risk Assessments by the Western Australia, Queensland and the Northern Territory Governments, all of which concluded that gamba grass is an extremely high risk environmental weed. Gamba grass has invaded iconic areas that support some of Australia's most important natural values and Indigenous cultures: the World Heritage listed Kakadu National Park, Arnhem Land, Cape Work Peninsula and the east Kimberley. Unless gamba grass is banned and controlled it will soon rank amongst the very worst of exotic introductions, on a par with rabbits and cane toads. The difference is that the planting of gamba grass is being allowed in full knowledge of its damaging impacts. A Queensland Government assessment recommended a ban more than two years ago, but as yet no declaration has occurred. Northern Australia's tropical savannas are the largest and least damaged tropical savannas existing in the world today. We urge that you act quickly to stop these savannas from becoming further infested by gamba grass, preventing the degradation of this valuable ecological asset.


Weeds CRC Communications Team CRC for Australian Weed Management PMB 1, Waite Campus Glen Osmond SA 5064