Invasive plants fact sheets

The tiny leaf-beetle, Nesaecrepida infuscata, a biological control agent released on the weed Mimosa pigra in northern Australia, attacks the roots and leaves.

Biological control of Onopordum thistles is leading to greater productivity from formerly heavy thistle infested pastures in south-eastern Australia.

The pasture weeds, Cape tulips, are considered suitable targets for biological control because there are few close relatives among Australian native species and no related crops.

The biocontrol agent, red apion, was released on the weed, Emex, mainly in the Western Australian wheat belt, but it failed to establish here.

Larvae of the red apion, released in Australia as a biocontrol agent for the weed, Emex, tunnel through the plant reducing its vigour and indirectly decreasing seed production.

The introduced weed, Emex, which costs A$40 million a year in crop losses and production costs in Western Australia alone, has been the target of a biolgical control program.

CSIRO researchers have successfully released biological agents to attack Onopordum thistles that thrive in high fertility soils in south-east Australia.

Scotch broom is an introduced weed threatening environmental, forestry and grazing land in higher rainfall areas of South-Eastern Australia.

CSIRO investigated possible biological control options for the introduced plant, blue heliotrope, which is now a major weed in some areas.

Infestations of the aquatic weed, salvinia, disrupted waterways in tropical countries but biological control using a tiny weevil brought it under control in many places.