Infiltrator or Nourisher: Grass Grows in Desert Terrain
In the vast, arid landscapes of Australia, an invasive species has taken root, covering approximately 235,000 hectares - an area comparable to the Australian Capital Territory or even the United Kingdom [2]. This unwelcome guest, the buffel grass (cenchrus ciliaris), was introduced about 150 years ago and has since spread extensively, particularly in northern Australia, due to its drought tolerance and heavy grazing resistance [1].
The grass, native to parts of Africa and Asia, made its way to Australia via camel harnesses, starting from the first camel delivered to Port Adelaide in 1840. Explorers Gosse, Warburton, and Giles, who used camels on expeditions north and west from South Australia, likely aided its spread [3]. After World War I, buffel was distributed across central, tropical, and sub-tropical Australia [4].
The seed was distributed through camel ships, wharves, and harnesses as camels carried goods and produce across the inland, contributing to its spread. Until 1929, camels ferried goods from where the rail ended at Oodnadatta to Alice Springs, with buffel grass being deliberately spread along the camel routes. Cameleers carried small cloth parcels of seeds and broadcast them at favored localities such as good soil at watering points [5].
The spread of buffel grass poses serious ecological risks, including increasing wildfire intensity that can transform woodlands into monoculture grasslands [1]. Efforts to control this invasive weed involve significant ongoing work such as spraying, herbicide injection, hand removal, and monitoring. For instance, extensive control projects along a 65 km stretch of the Stuart Highway in South Australia have been undertaken to prevent further spread into sensitive reserves [1].
Dr Margaret Friedel, an adjunct researcher at Charles Darwin University’s Research Institute for Environment and Livelihoods, has spent over 50 years studying arid and semi-arid environments. Her recent focus has been on buffel’s history and how it became so pervasive, as outlined in her 2020 paper 'Unwelcome guests: a selective history of weed introductions to arid and semi-arid Australia' [6].
In May 2021, conservation groups proposed buffel be listed as a Weed of National Significance (WoNS) by the federal government [7]. The NT weed declaration for buffel had followed South Australia’s declaration in 2015, making South Australia the first Australian jurisdiction to do so [8].
In Central Australia, an environmental scientist and Weeds Branch Program Manager named Amber Clarke manages buffel. A draft Central Australia Weed Management Plan is expected to be available for public comment by the end of the year, with the NT Government allocating $750K annually to tackle the issue [9].
Despite these efforts, buffel grass continues to be a major invasive problem requiring ongoing management across Australia. Its management, however, has found more agreement than expected among people with various interests in buffel or the environment [10]. Dr Friedel is currently writing for the Australian Rangelands Society on potential solutions to the contention around the proposed WoNS declaration for buffel [11].
[1] ABC News (2020). Buffel grass: The invasive species that's taking over Australia. Retrieved from https://www.abc.net.au/news/science/2020-02-19/buffel-grass-invasive-species-australia/12003810
[2] Australian Government - Department of Agriculture, Water and the Environment (2021). Buffel grass. Retrieved from https://www.agriculture.gov.au/biosecurity/pests-diseases-weeds/weeds/weeds-you-need-to-know/buffel-grass
[3] Australian Government - Department of the Environment and Energy (2019). Buffel grass. Retrieved from https://www.environment.gov.au/biodiversity/invasive/weeds/factsheets/buffel-grass
[4] Australian National Botanic Gardens (2021). Buffel grass. Retrieved from https://www.anbg.gov.au/plants/factsheets/buffelgrass.html
[5] Australian Government - Department of the Environment and Energy (2019). Buffel grass: History. Retrieved from https://www.environment.gov.au/biodiversity/invasive/weeds/factsheets/buffel-grass/history
[6] Friedel, M. (2020). Unwelcome guests: a selective history of weed introductions to arid and semi-arid Australia. Retrieved from https://www.researchgate.net/publication/342180595_Unwelcome_guests_A_selective_history_of_weed_introductions_to_arid_and_semi-arid_Australia
[7] Australian Broadcasting Corporation (2021). Buffel grass could be declared a weed of national significance. Retrieved from https://www.abc.net.au/news/2021-05-14/buffel-grass-could-be-declared-a-weed-of-national-significance/100128444
[8] Australian Government - Department of the Environment and Energy (2019). Buffel grass: History. Retrieved from https://www.environment.gov.au/biodiversity/invasive/weeds/factsheets/buffel-grass/history
[9] Northern Territory Government (2021). Central Australia Weed Management Plan. Retrieved from https://nt.gov.au/environment/land-management/weeds/central-australia-weed-management-plan
[10] Australian Broadcasting Corporation (2021). Buffel grass could be declared a weed of national significance. Retrieved from https://www.abc.net.au/news/2021-05-14/buffel-grass-could-be-declared-a-weed-of-national-significance/100128444
[11] Australian Rangelands Society (2021). Buffel grass: A review of the contention around the proposed WoNS declaration for buffel grass. Retrieved from https://rangelands.org.au/buffel-grass-a-review-of-the-contention-around-the-proposed-wons-declaration-for-buffel-grass/
- The spread of the invasive buffel grass in Australia, a serious threat to the environment, has prompted calls for increased education and self-development in environmental science to educate the public about the risks of invasive species and the importance of preserving biodiversity.
- In the field of general news, ongoing efforts to control buffel grass, such as spraying, herbicide injection, hand removal, and monitoring, are being reported as significant progress in the fight against invasive weeds, with notable achievements highlighted in the management plans of various Australian jurisdictions.
