Invasive weeds are among the most serious threats to Australia's natural environment and primary production industries. Weeds have major economic, environmental and social impacts in Australia, causing damage to natural landscapes, agricultural lands, waterways and coastal areas.
Australia spends considerable time and money each year in combating weed problems and protecting ecosystems and primary production on private and public land. Weed problems are complex, with multiple causes, and efforts to reduce their impacts must be coordinated across all sections of society.
A weed is any plant that requires some form of action to reduce its effect on the economy, the environment, human health and amenity. Weeds typically produce large numbers of seeds, assisting their spread and are often excellent at surviving and reproducing in disturbed environments. A weed can be an exotic species or a native species that colonises and persists in an ecosystem in which it did not previously exist. Weeds can inhabit all environments; from our towns and cities through to our oceans, deserts and alpine areas.
Some weeds are of particular concern and, as a result, have been listed for priority management or in legislation.
- Twenty Weeds of National Significance (WONS) have been identified because of their invasiveness, impacts on primary production and the environment, potential for spread and socioeconomic impacts.
- The National Environmental Alert List (the Alert List) for environmental weeds identifies 28 plant species that are in the early stages of establishment and have the potential to become a significant threat to biodiversity if they are not managed.
- Sleeper weeds are plants from overseas that have currently established only small wild populations but have the potential to spread widely.
- There are six species targeted for national eradication under the Natural Resource Management Ministerial Council's National Cost-sharing Eradication program.
- Some weeds are listed as target species for biological control through a cross-jurisdictional government process that allows for research on biological control for that weed.