THE COMPARATIVE EFFECTIVENESS OF CHEMICAL TRAPS, AND FIR, SPRUCE AND LARCH BILLETS, FOR THE ESTIMATIONS OF PINE WEEVIL (HYLOBIUS-ABIETIS L) (COL, CURCULIONIDAE) DENSITY INDEXES

The pine weevil (Hylobius abietis) is attracted to damaged conifer species by the release of the volatiles alpha-pinene and ethanol. Recent attention has focused on the effectiveness of these Volatiles in attracting the weevils to chemical traps. This study, in reforested clearfell areas, found that chemical traps were less effective than three species of conifer billet traps. In plantations of Douglas fir and Japanese larch, where these species were also used as billet traps, the comparative effectiveness of Sitka spruce billets was always greater. It is concluded that there is still a significant role for billet traps in studies of weevil activity and densities.