Environmental weeds are plants that invade native ecosystems and adversely affect the survival of indigenous flora and fauna.
Environmental weeds can be foreign plants accidentally or intentionally introduced into Australia, or they can be native plants that have become weedy due to inappropriate management, or because they are outside of their normal range.
Environmental weeds may have significant economic and social impacts, as well as environmental impacts, including:
- reduction of biodiversity
- cost of control
- loss of ecotourism opportunities
- impacts on recreational activities
- impacts on landscape
- degradation of water quality
- increased risk of fire.
An environmental weed is one that is directly impacting our native biodiversity. It can be a species that is prohibited or restricted under legislation or not . It is what that plant is doing to damage the environment that defines it as an environmental weed.
Many environmental weeds were originally introduced as garden ornamentals. Introduced plants that are climatically suited to their new environment can thrive and out-compete native species because of the absence of natural diseases, insects and pests.
As the majority of environmental weeds are not listed under their species names on herbicide registration, an off-label permit has been approved by the Australian Pesticides and Veterinary Medicines Authority (APVMA) to help departmental, local government and environmental groups, and people generally manage these pest plants.