An ambrosia beetle in radiata pine.  J. A. Harris and G. Minko.  September 1980.  10 pp. (unpubl.)

SUMMARY

The ambrosia beetle Xyleborus saxeseni (Ratzeburg) (Coleoptera: Scolytidae) is indigenous to both Europe and North America; and in Victoria, was first detected in plantations of Pinus radiata D. Don near Bright in 1956, and later, in windthrown P. radiata trees near Myrtleford in 1968. Colonies of the beetle were again found in 1979 in P. radiata near Myrtleford, but only in trees injected with glyphosate, a herbicide used for chemical thinning purposes. Glyphosate may act by inhibiting the biosynthesis of aromatic amino acids, and this inhibition may increase the attractiveness of the host trees to the beetles. As it appears to be easier to attract ambrosia beetles than to destroy them, attraction and trapping techniques may provide the most effective solutions to ambrosia beetle problems. Glyphosate may be a suitable attractant in pine plantations.

The economic significance of the beetle in pine appears to be small, though infested logs would be unacceptable for export because of stringent quarantine regulations that disallow the shipment of timber with conspicuous borer damage. The use of trap-trees may also be an effective solution to the ambrosia beetle problem in stands of Eucalyptus nitens and E. delegatensis in Victoria.

Also published:

Harris, J.A. and Minko, G. (1980)  An ambrosia beetle in radiata pine.  For. Comm. Vic., For. Tech. Pap. 28: 26-31.