Population dynamics of St. John's wort in south-eastern Australia
D.T. Briese, CSIRO Entomology and Co-operative Research Centre for Weed Management Systems, GPO Box 1700, Canberra, ACT 2601, Australia.
Summary
A thorough understanding of the ecology of St. John's wort and the processes that drive the population dynamics of infestations is a key to the management of this weed. However, while some aspects of the weed's biology have been studied in the seventy years of research on its control in Australia, there has been only one study devoted to its ecology; in the Ovens Valley, Victoria, over a two year period. To complement this detailed work and provide a picture of longer term fluctuations, four St. John's wort populations were monitored over a period of seven years, from 1981-87. This paper summarizes the type of data collected, and uses it, together with that from the Ovens Valley study, to define those properties of St. John's wort that have contributed to its success as a weed and which may render it vulnerable to particular methods of control.
Plant Protection Quarterly (1997) 12 (2) 59-63.