Gamba Grass was introduced as a pasture grass, and is still
popular with some pastoralists because of its high biomass
production. Gamba Grass can grow as tall as 4 metres, producing
fuel loads for fires that are four to ten times greater than native
grass fuel loads. This change in fire regime is causing concern, as
over time hotter fires may be transforming the savanna landscape
into grassland, killing the trees. The seeds of this grass spread
mainly by wind and water, although vehicles and machinery can also
transport seed in mud and radiators. The grass can also spread
effectively into undisturbed areas where its grows very
quickly.
By burning the Gamba Grass at the end of the wet season before
it flowers, reproduction of the grasses can be minimised. Heavy
grazing can also reduce the biomass of the grass. Some chemicals
can be used for control; however this can be expensive over large
areas.
Articles
Effects of canopy cover and ground disturbance on establishment of an invasive grass in an Australia savanna
Discussion on Gamba's grasses preference for establishing on disturbed and undisturbed sites [
read more...]
Evidence in on the impact of gamba grass
Concerns about the potential environmental impacts of gamba grass ( Andropogon gayanus ) were first raised in the early 1990s However the push for effective and coordinated control strategies were hampered by the lack of published scientific… [
read more...]
Exotic Grasses and Fire
Discusses the effect of fire on Gamba and Mission Grass [
read more...]
Frillneck Lizard (Chlamydosaurua kingii) in Northern Australia – determining optimal fire management regimes
Reviews the impact of fire on frill neck lizard habitat [
read more...]
Gamba grass in Wildman River National Park
I was interested in the article by David Bowman in the last issue (Issue 10 Introduced grasses triumph or Trojan horse see link below ) I have just completed an Honours project investigating infestation of gamba grass in Wildman… [
read more...]
Introduced grasses: poor master, but useful servant
Agricultural consultant Trevor Howard looks at some strategies the grazing industry and government are implementing to help contain exotics while reaping the benefits. Discusses the impact of exotic grasses on fire hazard. From Savanna Links, Issue 16, Oct - Dec 2000 [
read more...]
Introduced grasses: triumph or Trojan horse?
David Bowman of the Northern Territory University argues that one of the most profound threats to the tropical savannas is developing under our noses yet little research is being carried out on the issue Over the past… [
read more...]
Managing Perceptions
Identifies the key issues in fire managemenet in northern Australia [
read more...]
Testing the grass-fire cycle: alien grass invasion in the tropical savannas of northern Australia
Compares fuel loads in areas invaded by Gamba grass with areas dominated by native grasses and discusses how Gamba grass contributes to the grass fire cycle. [
read more...]
The Impact of fire on Gamba Grass
Outlines the potential impact of the spread of Gamba Grass in the Northern Territory, also contains links for further information about identification, control and management of the species. [
read more...]
Weed invasion risks
Habitats at risk, weed targets and weeds of concern in Arnhem land. [
read more...]
Links
ABC Country Hour: Territory fire issues demand some answers
www.abc.net.au/rural/nt/stories/s1367055.htm
Jack Ellis talks to Professor David Bowman about the impact of African grasses such as mission, para, buffalo and gamba grass. (ABC Country Hour, 12 May 2005)
Biosecurity Queensland Factsheet: Gamba Grass Andropogon gayanus
www.dpi.qld.gov.au/documents/Biosecurity_EnvironmentalPests/IPA-Gamba-Grass-PP147.pdf
This factsheet describes Gamba Grass: what it looks like, its history of cultivation in Australia, why it is a problem, where it grows in its native range and in Queensland, its weed status in Queensland, and methods of control
Biosecurity Queensland web page for Gamba Grass Andropogon gayanus
www.dpi.qld.gov.au/cps/rde/dpi/hs.xsl/4790_10143_ENA_HTML.htm
This web page on the Biosecurity Queensland web page provides information on Gamba Grass, including what ot looks like, where it grows, its uses, why it is a problem, and its weed status in Queensland. It also provides links to useful resources.
CSIRO Gamba Grass Research
www.terc.csiro.au/research.asp?Program=LANDECOL&Project=EXOTICPLANTS
Information on research into Grassy weeds in northern Australia being undertaken by TS-CRC, CSIRO and Charles Darwin University to address the current lack of knowledge on the ecology and impacts of exotic grasses in tropical savannas
Ecoport profile for Gamba Grass Andropogon gayanus
ecoport.org/ep?Plant=3202&entityType=PL****&entityDisplayCategory=full&menuStyle=text
This profile of Gamba Grass Andropogon gayanuson FAO's Ecoport Web Site, provides information on the appearance, distribution, ecology, status and use of the species. Links are provided to maps, illustrations and other resources. Information is incomplete for many species, but is being continually upgraded.
Gamba Grass - ABC Stateline NT program - 04/08/2006
www.abc.net.au/stateline/nt/content/2006/s1706847.htm
Melinda James interviews scientists and land managers about Gamba Grass
Gamba Grass Action Group - NT
www.gamba.org.au
GAG (NT)’s aims to educate people about the serious environmental impact Gamba Grass, and to prevent the further spread of Gamba throughout the Northern Territory and northern Australia.
Gamba Grass declaration in the Northern Territory
newsroom.nt.gov.au/adminmedia/mailouts/4801/attachments/Gamba%20Declaration%202511.pdf
A press relaease from Alison Anderson, Minister or Natural Resources, Environment, the Arts and Sport, announcing the declaration of Gamba Grass as a weed in the Northern Territory. It states that a BC classification for Gamba Grass in the Darwin to Katherine area will require landholders to manage and control the weed's spread. Gamba Grass eradication is required elsewhere in the Northern Territory, where the weed has an AC classification. New plantings and importation of seed will be prohibited throughout the Territory.
Gamba Grass Management Guidelines
www.nt.gov.au/nreta/natres/weeds/ntweeds/gamba/pdf/gamba_mngt_guide.pdf
The introduced pasture gamba grass ( Andropogon gayanus) , is now the subject of a new management guide from the Northern Territory. The NT Department of Natural Resources, Environment and the Arts (NRETA) has developed the guide as a tool for all land managers to help identify and manage the grass. It provides a four-step approach to managing gamba to either eradicate it, prevent its spread, or use it as a pasture.
The guide explains how to assess the situation, develop and implement plans and monitor and review. The guide also has photos to help identify gamba throughout its life cycle.
NRETA is leading a joint initiative in collaboration with the Department of Primary Industries, Fisheries and Mines and Charles Darwin University to develop a Weed Risk Assessment System for the entire Territory.
Currently gamba grass is not a declared weed in the NT or Queensland, but in the NT it is being tested under the draft model WRA to be considered for declaration under the Weeds Act. The Weed Management Branch of NRETA is also undertaking community education and awareness of the environmental impacts of gamba and ways to identify and manage the grass species.
In Queensland, where the grass was recently identified in Queensland’s Burdekin region, a preliminary assessment has been done and is currently under consideration by Queensland’s Dept. Natural Resources, Mines and Water.
Gamba Grass Zones in the Northern Territory
www.nt.gov.au/nreta/natres/weeds/ntweeds/gamba/management_zones.html
A map on the NRETAS website showing the Management Zone in which Gamba Grass must be controlled and its spread contained (Darwin to Katherine area), and the Eradication Zone, where Gamba Grass must be removed (rest of the Northern Trritory)
Katherine Regional Weed Management Strategy 2005-2010
www.nt.gov.au/nreta/natres/weeds/management/regional/index.html
This document produced by NT Department of Natural Resources, Environment and The Arts prioritises weed management issues and programs in the Katherine region.
Map of Gamba Grass in the Northern Territory
www.nt.gov.au/nreta/natres/nht/inrm/maps/pdf/map21150405.pdf
Map of Gamba Grass in the Northern Territory- appendix to the Northern Territory Interim Natural Resource Management Plan
Mission and Gamba Grass
www.drytropics.org/weeds_mission_gamba_fire.htm
Provides information about the species' current distribution, fuel loads, management approaches and costs to the community.
NT Agnote: Kent Gamba Grass
transact.nt.gov.au/ebiz/dbird/TechPublications.nsf/26221F815DCB8D7769257233004DDDBA/$file/413.pdf
Information leaflet on the Northern Territory Government's Department of Business, Industry & Resource Development Web Site
NT Agnote: Management of Kent Gamba Grass
transact.nt.gov.au/ebiz/dbird/TechPublications.nsf/27F0462B05D7D1C569257235004A9671/$file/672.pdf
This leaflet describes the characteristics of Gamba Grass, including its potential fire hazard when not adequately grazed. It stresses that The Northern Territory Government does not support new sowings of Gamba Grass, and describes control measures for non-pastoral areas.
PIER Profile for Gamba Grass Andropogon gayanus
www.hear.org/Pier/species/andropogon_gayanus.htm
PIER Profile for Gamba Grass Andropogon gayanus on the Pacific Island Ecosystems at Risk Web site.
Information listed includes Status on Pacfic Islands; Common and scientific names across the region; Species description; Habitat/ecology; Methods of propagation; Native distribution; Distribution elsewhere; Other information sources; and, where available, Illustrations and a Weed Risk Assessment
The Conservation Threat of Weeds in Savanna Woodlands
www.nt.gov.au/nreta/wildlife/programs/threats/weeds.html
This article, on the NT Department of Natural Resources, Environment, the Arts and Sport website, descibes the threat Gamba Grass and Mission Grass pose to wildlife in the Darwin-Daly region.
The Gamba Declaration
www.invasives.org.au/downloads/gambadeclarationforsign-on.pdf
An open letter from scientists calling for a ban on
Gamba grass across Northern Australia. It describes the threat to habitats, its invasive nature, its impact on fire regime and tree death, its impact of nitrogen and carbon budgets, its reduction of water availability, and its threats to biodiversity and human life and property.
Tropical Grasslands Society description of the pasture plant Gamba grass Andropogon gayanus
www.tropicalgrasslands.asn.au/pastures/gamba_grass.htm
Tropical Grassland Society of Australia description of the pasture plant Gamba grass Andropogon gayanus, written by L.R. Humphries and I.J. Partridge, describing the characteristics of the plant and its suitability for tropical and subtropical pastures in Australia
University Gamba grass study essential viewing
www.cdu.edu.au/newsroom/stories/2004/september/gambagrass/
"The impacts of Gamba grass" as featured on ABC TV science program, Catalyst
WA Florabase Profile for Gamba Grass Andropogon gayanus
florabase.dec.wa.gov.au/browse/flora?f=031&level=s&id=17651
WA conservation status and taxonomic information for the plant Gamba Grass Andropogon gayanus), and, when available distribution map and illustration, from FloraBase - The Western Australian Flora
Visit About FloraBase for information on WA FloraBase
Citation details: Western Australian Herbarium (1998-). FloraBase - The Western Australian Flora. Department of Environment and Conservation).
http://florabase.dec.wa.gov.au/
Weed CRC factsheet: Under Pressure - Australian flora and fauna threatened by invasive plants
www.weedscrc.org.au/documents/fs44_threatened_species.pdf
This factsheet, on the Weed CRC Web Site, describes how threatened species have been affected by weeds. Tropical species discussed are
Purple-crowned fairy-wren Malurus coronatus coronatus, threatened by grazing and trampling of their riparian habitat by cattle, and subsequent weed invasion and changes to fire regimes;
Julia Creek dunnart Sminthopsis douglasi, threatened by over-grazing, predation by feral cats and weed invasion by prickly acacia Acacia nilotica
and changes to fire regimes;
Atlas moth Attacus wardi, threatened by urban growth, and the invasion by giant African grasses such as gamba grass Andropogon gayanus; and
Yellow chat Epthianura crocea tunneyi, threatened by grazing by cattle, changed fire regimes and the invasion of their floodplain habitat by mimosa Mimosa pigra, para grass Brachiaria mutica and gamba grass Andropogon gayanus
Weeds Australia Identification Guide: Gamba Grass Andropogon gayanus
www.weeds.org.au/cgi-bin/weedident.cgi?tpl=plant.tpl&state=&s=&ibra=all&card=G04
This identification guide, on the Weeds Australia Web Site, includes photos, a description of the plant, notes on its distinguishing features and its dispersal ability, and a map of its current and potential distribution
Weeds compromise fire management: Gamba grass in northern Australia
www.environment.gov.au/soe/2006/publications/integrative/fire/case-study-2.html
A description of the threats caused by Gamba Grass to biodiversity, human life and property
Woodland to Grassland: the future for the Top End
tenpsnt.tripod.com/newletters/TENPSSuppl_May04.pdf
This article by Mark Raines, written for th Top End Native Plants Society, describes a study of fire impacts in Charles Darwin National Park by Dave Liddle. This study found that in native pastures, the population of Armstrong's Cycads is unlikely to change over 100 years. However, with increased fuel loads, equivalent to those produced by Gamba Grass, the population of cycads will collapse to around 10% of its original size over the same period. Increased mortality was also observed for Ironwood
(Erythrophleum chlorostachys), Woollybutt (Eucalyptus miniata), Stringybark (Eucalytpus tetrodonta), Cocky Apple (Planchonia careya) and Billy Goat Plum (Terminalia ferdinandiana).
