HOST RECOGNITION AND AGGREGATION BEHAVIOR OF HYLASTES-CUNICULARIUS ERICHSON (COL, SCOLYTIDAE) IN THE LABORATORY

Host recognition and aggregation behaviour in the black spruce beetle, Hylastes cunicularius Erichson, were studied in choice experiments in the laboratory. The beetles tended to aggregate. Aggregation occurred at host material or at beetles and was independent of the sex of the beetles. Hidden host material was found by active host orientation. The beetles were attracted by several conifer species. In some experiments the beetles preferred the main host, Norway spruce, but Scots pine was also readily accepted. Sections of roots were chosen more often than stem sections. Fresh cuts on the host material enhanced attraction. No evidence was found to indicate the presence of an aggregation pheromone.