Weed risk management (WRM) systems have been designed to quantify the relative risks that different weed species pose. This paper reports on the development of a large database of Weed Risk Management assessments for Australia. From a survey of several sources, some 834 taxa were regarded as potential problem weeds in Australia. These taxa were prioritised using a protocol for initial weed risk assessment and the higher risk weeds were included in a reduced list of 268 taxa for more detailed assessment. Initially risk assessments are being conducted for New South Wales (NSW). Other state and territory colleagues will be able to modify these, and upload these and other species assessments onto the database. The assessments will be made available on the internet in a searchable database form after the database has been piloted using the assessments for new and emerging weeds from NSW.

One Australian definition of a weed: “…a plant, which has, or has the potential to have, a detrimental
effect on economic, conservation, or social values in Australia...” encompasses the negative impacts of a variety of
species on Australia’s agriculture, unique environment, biodiversity and society. Most of today’s weed species were
initially introduced to Australia at the time of European colonization in 1788 as potentially beneficial plants, often
for ornamental purposes, and for various agricultural and environmental benefits: relatively few were accidentally
introduced. Weeds in Australia reduce farm and forest productivity, displace native species, and contribute to land
and habitat degradation, thereby threatening the sustainability of natural ecosystems and primary production. They
may also cause allergies, and some are poisonous plants. Heavy infestations reduce recreational opportunities, and
biodiversity values of natural areas. A relatively conservative estimate suggests that the annual economic costs of
weeds to Australia’s primary industries exceeds AU $4 billion.
On a national level, the National Weed Strategy guides weed management, coordinated across Australia’s
States and Territories. It places emphasis on integrating the four approaches: Prevention, Eradication, Containment
and Asset protection, which can be thought of as matching the invasion process of a weed species - from pre-entry
through to widespread establishment. The approach is flexible, allowing land managers to take action in response to
a specific or local situation; or to implement broader weed management, at regional, state or national level. Weed
legislation, and protocols for Weed Risk Assessments (WRAs) are an integral part of managing plant introductions,
and future weed problems in Australia. Guidelines, tools and techniques to implement weed management across
varied landscapes include the use of registered herbicides, integrated with mechanical, cultural and biological weed
control options, and others, such as the use of fire, animal grazing and bush regeneration. Emerging weed issues
include the impacts of climate change on the distribution of weed species; excessive herbicide use; development of
herbicide resistance in major agricultural weeds; and the potential impacts of genetically-modified organisms.
Keywords: Australian weeds; Weed Risk Assessments, Weeds of National Significance

Weed risk management (WRM) systems have been designed to quantify the relative risks that different weed species pose. This paper reports on the development of a large database of Weed Risk Management assessments for Australia. From a survey of several sources, some 834 taxa were regarded as potential problem weeds in Australia. These taxa were prioritised using a protocol for initial weed risk assessment and the higher risk weeds were included in a reduced list of 268 taxa for more detailed assessment. Initially risk assessments are being conducted for New South Wales (NSW). Other state and territory colleagues will be able to modify these, and upload these and other species assessments onto the database. The assessments will be made available on the internet in a searchable database form after the database has been piloted using the assessments for new and emerging weeds from NSW. Keywords WRM, weed risk assessment, potential problem weeds.