25 February 1999
WEEDS THREATEN RURAL AREA
A weed reduction campaign will be launched at 2 pm, Thursday, 25 February, at the Peter McAulay Centre (police headquarters), with posters, pamphlets, and a community service announcement produced by the Department of Primary Industry and Fisheries (DPIF). Speaking at the conference will be:
. Dr Garry Cook, CSIRO
. John Whatley, Regional Fire Control Officer, Vernon Region, Bushfires Council of the NT
. John Brock, Litchfield vegetation officer
Also present will be Station Officer Dave Pettit of the NT Fire and Rescue Service and John Pitt, Weed Control Officer of DPIF.
Bob West of Delta Productions has broadcast quality copies of the tapes. Gamba grass was introduced to Australia from West Africa in the 1930s. In the 1980s, it was planted around the Top End to improve pastures. In 1999, the introduced species has been recognised as a serious environmental threat in the Territory.
"Gamba grass produces huge fuel loads, which makes fires difficult to control. It grows very fast and is costly to get rid of once it becomes a problem," says Dr Garry Cook of the CSIRO.
"The best time to get rid of it is just as it is starting to establish, before it drops seeds.
"At present, the grass is well-established in the Darwin rural area, down the Stuart Highway from here to Adelaide River, scattered south from there and down through the Daly River area," Dr Cook said. "It has established in areas where there is a lot of human activity, such as rural blocks, horticultural areas and orchards."
Dr Cook, who studied Gamba grass in West Africa, says it is now classified as an environmental weed and presents a major fire risk in the Darwin rural area because:
it produces up to five times more fuel than native grasses,
fires in Gamba grass burn hotter and spread faster,
Gamba grass often grows along firebreaks and fence lines, which is often where firefighters are trying to access fires to control them,
many native trees are less tolerant of intense fires than Gamba grass, which may lead to native plants being killed off, compounding the spread of the grass.
"In time, dense stands of Gamba grass could replace the native woodlands, as trees are killed by the intense fires. This is similar to how the plants grows in its native West Africa," he said.
"We need to stop this grass spreading and to control existing outbreaks. This can be done mechanically or with herbicides. Careful burning during the wet season is a possible means of reducing the risk of uncontrollable fires in the dry season, but this alone will not control it."
Concerns about the spread of both Gamba and Mission grass in the Top End have led to a unique coalition of community and conservation groups, fire services and Government Departments working on integrated research, fire control and land management strategies.
The groups are concerned at:
the increased number of wildfires across the Vernon area and the need to reduce fuel loads;
the rapid encroachment of weeds such as Mission and Gamba grasses on rural blocks.
"Gamba and mission grasses are prolific seeders," says DPIF weeds coordinator John Pitt. "This is the time of year when they start to seed, so it is vital that all rural residents slash their properties before the weeds start seeding."
John Whatley, Regional Fire Control Officer, Vernon Region, of the Bushfires Council of the NT said a failure to clear blocks created a major fire hazard each year.
"The welfare of volunteers is our primary concern. The increased intensity of fires burning this type of fuel makes suppression activities inherently more dangerous. It is the landholder's responsibility to manage fuel on their land," he said.
"Mission Grass is a registered weed, and shouldn't be growing anyway. But it can also be an offence for people to have heavy fuel loads on their property," Mr Whatley said.
A cooperative effort between the following organisations is believed to be the most comprehensive approach ever taken in Australia to land management and fire control.
Territory (DPIF, PAWA, Department of Transport and Works, Department of Lands Planning and Environment, and Parks and Wildlife),
Local Governments (Litchfield Shire and the Local Government Association);
community and conservation groups such as the Vernon Land Management Group and Greening Australia;
and the two Fire Services (Bushfires Council and Fire and Rescue Service)
The Fire Services have negotiated with responsible Government agencies for the reduction of fuel loads on Crown land, while the Department of Transport and Works has sprayed to control Mission and Gamba grass on verges.
However, all property owners have a responsibility to look after their own blocks, says Litchfield vegetation officer John Brock.
"Land management is important for both private and public landowners. Everyone needs to take on board the issues and put in place effective controls to keep the problem under wraps," Mr Brock said.
Natural Heritage Trust
The Vernon Land Management Group was recently funded by the Bushcare Program of the Natural Heritage Trust to employ a scientist to coordinate techniques to reduce fire and weed problems in the rural area and determine a scientific approach for the control of Mission and Gamba grasses.
The Federal grant was based on in kind support from Transport and Works and Local Government Association of the Northern Territory (LGANT) and is being coordinated by Mr Brock.
The project is designed to reduce fuel on rural blocks and road verges, reduce the threat of uncontrolled wildfires to rural blocks in the Dry, and preserve valuable native habitats.
"Mission and Gamba grass are introduced species which endanger native vegetation and produce up to four times the fuel litter of native grasses," Mr Brock said. "With more people moving to the rural area, we are concerned at the potential for disaster if the weeds are not brought under control.
"We have a unique rural lifestyle in the Territory. This project will improve the condition and quality of diverse natural vegetation to better conserve regional biodiversity.
"It should also help identify habitats of conservation significance which are under threat from uncontrolled wildfire, invasive species and changing land use, and develop management strategies for more effective protection of these areas.
"The project will use existing fire and vegetation data to formulate integrated strategies for long-term fire and vegetation management in the Vernon Region. Information from the project will be linked to the NT weeds database.
Vernon Land Management Group
The Vernon Region covers a 1200 square kilometre area including the Darwin and Palmerston municipalities, the Shires of Litchfield and Coomalie, the Belyuen and Cox Peninsulas, and the Finniss, Warrai and parts of the Marrakai sub-regions. Land uses in the area include rural residential, agricultural, pastoral, conservation and Aboriginal Land Trust.
For some time, there has been concern by a range of community, industry and Government agencies, including the Territory's two fire authorities, regarding the increased frequency and intensity of uncontrolled wildfires. These fires have resulted in extensive damage to property, economic losses, and land degradation.
Of particular concern is the spread of introduced perennial species such as Mission and Gamba grasses. These grasses have four times the fuel load of native species.
Cooperation between the Bushfires Counil of the NT, NT Fire and Rescue Service, Greening Australia and CSIRO has seen Wet season burn-offs used as one strategy to reduce the fuel load and the Fire and Rescue Service has developed better fuel reduction practices.
DPIF has reviewed its policy on Gamba grass and no longer recommends its planting. DPIF has begun herbicide trials in non-pastoral areas. A demonstration site was established through cooperation between DPIF, Transport and Works, Greening Australia NT and the Litchfield Shire Council to help manage invasive species on a road reserve.
A committee was established to provide a united approach to the problem. This committee, the Vernon Land Management Group, identified the need for a more effective integration of fire, vegetation and weed management strategies.
Media Relations and Corporate Communication
NT Police, Fire and Emergency Services
Contacts CSIRO Gary Cook 8944 8400
Greening Australia Mike Clark 8981 1344
Bushfires Council John Whately 8976 0089
DPIF John Pitt 8999 2020
Lichfield John Brock 8983 1912
Fire and Rescue Service Dave Pettit 8946 4141