Potential Weed Threats
There are many weeds which may threaten our environment and industries that are not yet here or are not yet declared as invasive.
It is everyone's responsibility to avoid future weed establishment from either accidental or intentional plant introductions.
Quarantine
International
Australia has strict quarantine laws which determine what can and can't be brought into the country. International travellers should be careful to check any clothing, footware, mud, camping gear etc for seeds or plant material. You should also be weary of purchasing products such as cushions or toys which may be stuffed with plant material or seeds. When travelling, always declare anything you are not sure of, so qualified inspectors can make necessary assessments. For more information go to the Australian Quarantine and Inspection Service (AQIS) web site.
Interstate
Many plants which have established interstate have the potential to spread into the NT. For example, rubber vine (Crytostegia grandiflora), a declared Weed of National Significance (WoNS), has already established throughout Queensland, a containment line has been established to try and prevent further spread in other states and territories.
Local
Cabomba (Cabomba caroliniana) is also a declared Weed of National Significance (WoNS). There have only been two outbreaks in the NT. The first, in Marlow Lagoon, was successfully eradicated, the second in Darwin River is currently being treated. A quarantine zone has been declared to stop spread from the affected area. For more information go to cabomba.
Cabomba
If you see any cabomba plants please notify the Weed Management Branch immediately.
Garden Thugs
Almost all of our national aquatic weeds were imported as ornamentals and many of the worst environmental weeds were intentionally brought into Australia as garden plants.
Stop your Plants from 'Jumping the Fence'.
Plants can spread vegetatively (by cuttings or suckers) or through seed dispersal. There are some simple steps which can be taken to stop plants spreading, gardeners should:
- purchase industry endorsed sterile hybrids;
- choose plants which do not produce vast quantities of seed;
- ensure seeds and cuttings can’t 'escape' down drains or watercourses;
- do not transport viable cuttings, fruits and seeds;
- do not dump plant material in bushland or at the dump, (if unsure burn or bury plants);
- do not dump fish tank contents into waterways and drains; and
- always remove seed from vehicles, machinery, clothing and domestic animals.
Choose Native Alternatives!
Our 'Garden Thug' brochure provides a list of beautiful native plant alternatives, which will also save on water and attract native birds and animals.
Garden Plants and Ornamentals which are now Declared Weeds
Unfortunately there are some garden plants, many of which were previously available for sale, that are now understood to be serious or potential threats. Once declared as a 'weed' under the NT Weeds Management Act plants are classfied as class A, B or C. These classifications determine if the plants should be eradicated, managed or disallowed into the NT respectively. The following are examples of plants which are now declared:
Class A - To be eradicated
- rubber vine (Crytostegia spp.)
- pond apple (Annoma glabra)
- mexican feather grass (Nassella tenuissa)
Class B - Growth and spread to be controlled
- lantana (all species and cultivars including Lantana camara and L. montevidensis);
- bellyache bush (Jatropha gossypiifolia); and
- candle bush (Senna alata).
Lantana
Aquatic Plants, formally sold by Retail Outlets, which are now Declared include:
- water hyacinth (Eichhornia crassipes)
- water lettuce (Pistia stratiotes)
- cabomba (Cabomba caroliniana)
- salvinia (Salvinia molesta)
Examples of Potential Threats:
- Neem ( Azadirachta indica)
- Yellow oleander (Cascabela thevetia)
- African tulip tree (Spathodea campanulata)
- Singapore daisy (Sphagneticola trilobata)
Further Resources
- Current list of weeds declared under the Weeds Management Act
- Weed Risk Management
