Progress towards the eradication of three melastome shrub species from northern Australian rainforests
Simon J. BrooksA, F. Dane PanettaB and Travis A. SydesC
A Cooperative Research Centre for Australian Weed Management, Tropical Weeds Research Centre, Biosecurity Queensland, Department of Primary Industries and Water, PO Box 187, Charters Towers, Queensland 4820, Australia.
B Cooperative Research Centre for Australian Weed Management, Alan Fletcher Research Station, Biosecurity Queensland, Department of Primary Industries and Water, PO Box 36, Sherwood, Queensland 4075, Australia.
C Biosecurity Queensland, Department of Primary Industries and Fisheries, PO Box 20, South Johnstone, Queensland 4859, Australia.
Summary
To eradicate a weed incursion, its extent must be delimited and each infestation extirpated. Measures for delimitation and extirpation are utilized to assess the progress of eradication programs currently targeting three melastome shrub species (Clidemia hirta, Miconia nervosa and M. racemosa) in north-eastern Australia. The main infested area for each species was determined during the year after initial detection, but expanded surveys have led to the discovery of isolated, smaller outlying patches. Programs are refining survey methods (including search frequency) to prevent reproduction. Weed incursions that are limited to single infestations represent a prime opportunity for eradication. However, population and dispersal data indicate that eradication will require an ongoing investment for some time for all three species. Highly persistent seed and dispersal by frugivores suggest that eradication may prove extraordinarily difficult should any of these species spread or be discovered at more locations.
Key words: Delimitation, extirpation, Melastomataceae, miconia, clidemia
Plant Protection Quarterly (2009) 24 (2) 71-78.