<i>Introduced bark beetles on exotic trees in Australia with special reference to infestations of</i>Ips grandicollis<i>in pine plantations</i>

Abstract

Summary Aspects of the biology, economic importance, causes of outbreaks and possible control strategies are briefly reviewed for bark beetles generally, and in particular, for the introduced species Hylastes ater, Hylurgus ligniperda, and Ips grandicollis in commercial plantations of Pinus spp., and for Phloeosinus cupressi and Scolytus multistrialus on ornamental cypress and elm respectively. The extensive plantations of Pinus radiata in Australia are believed to be especially susceptible to damage by bark beetles. Ips grandicollis can cause tree mortality and contribute to blue-staining in sapwood of pine, S. multistrialus is being monitored for a possible association with Ceralocystis ulmi (the causal agent of the devastating Dutch elm disease in Western Europe and North America), while H. ater, H. ligniperda and P. cupressi have low economic potential. Stringent plant quarantine measures need to continue at Australian ports of entry for timber and wood products, so that the risk of additional accidental introductions is minimised, particularly of aggressive species of the genera Dendroctonus, Ips and Tomicus.