A weed is a plant in the wrong place, outside its normal geographic range, with the potential to take over where it’s not wanted. Some previously well behaved plants have become outlaws in the Wet Tropics, thriving in local conditions, invading natural habitat and farmland, crowding out native species, or blocking waterways.
The number of known weed species in the Wet Tropics region has grown rapidly over the past 50 years to over 500 species. Their spread is increasing alarmingly (about 200 new weed species have been identified in the past decade). The majority of plant species which have become weeds have been intentionally introduced into the region for agricultural, horticultural or domestic purposes.
Weeds are generally associated with disturbed areas of ecosystems, although some may invade intact ecosystems. Many are highly invasive and can reproduce and spread rapidly in the absence of any natural controls. Weeds may disrupt ecosystems, compete with and replace native plants, reduce food and shelter for native species, change fire regimes and create soil erosion. Those weeds that can invade or transform pristine habitat are particularly threatening to the biodiversity of the World Heritage Area.
The Wet Topics Management Authority has produced a brochure which highlights the importance of biosecurity and management of invasive pests in the Wet Tropics. The brochure also stresses the need for education, research and community participation to help control a range of weeds, feral animals and diseases in the Wet Tropics. This includes collaboration between government agencies, local governments, landholders and industry groups.You can download a copy of the brochure below: