Centre for Plant Biodiversity Research
Wednesday 2 October:
Its not only the exotics that are escaping - our crops are getting away and even some of our natives are on the move.
Weed invasions pose a serious threat to biodiversity conservation in Australia. Introduced plants comprise 10-15% of the Australian flora and all Australian ecosystems are vulnerable to weed invasion. Most weeds of natural ecosystems were originally introduced to Australia for their ornamental values. These plants then 'escaped' from cultivated settings to invade bushland areas.
Weeds compete with indigenous plants for essential resources such as space, light, nutrients and moisture. In the worst cases, weed invasions can transform a healthy, diverse ecosystem into a barren monoculture. On the north coast of New South Wales, the invasive South African shrub, Bitou Bush, has reduced native plant diversity by 75 per cent in invaded coastal vegetation. Habitat opportunities for fauna are also altered as a consequence of weed invasion. Food, shelter and nesting resources may be lost as invasive weeds displace native plants.
Weed invasion contributes to the loss of biodiversity
and homogenisation of natural areas at the site, regional and landscape
scales. Weed control is therefore an essential component of remnant
vegetation management for biodiversity conservation.