Current distribution and status of Lantana camara and its biological control agents in Australia, with recommendations for further biocontrol introductions into other countries

Abstract

The results of surveys conducted in Australia over a five-year period (1996-2001) to determine the distribution of Lantana camara (lantana) and its introduced biological control agents are reviewed and discussed. The relative merits and drawbacks of each species are summarized for the benefit of other countries wishing to consider biological control programmes against lantana. Lantana is found in coastal and sub-coastal areas from far-north Queensland to southern New South Wales (NSW), Australia. Small populations of the weed have been reported around Darwin in the Northern Territory and Perth in Western Australia. For the purpose of this review, lantana is classified into five varietal groups, based on flower colour. The pink flowering group is the most common and widespread. It is the only variety found in southern NSW and in high altitude subtropical areas. The pink-edged red flowering varietal group is the next most common, being found from central NSW to far-north Queensland. The three remaining varietal groups, red, white and orange, are less common and limited in their distribution. Of the 30 biological control agents that have been introduced into Australia, 16 have established. The most widespread and damaging agents are Octotoma scabripennis, Uroplata girardi, and Teleonemia scrupulosa. Leptobyrsa decora is very damaging to lantana seasonally but has a very limited distribution, being found at only a few sites in high altitude tropical regions. Two agents, Plagiohammus spinipennis and Teleonemia harleyi previously reported as established, were not found in the surveys. Despite the establishment of 16 agents, lantana is not under adequate control in Australia. Climate is probably the major factor that prevents populations of insects from being maintained at consistently high enough levels to control the weed.