Selectivity of synthetic aggregation pheromones Linoprax(R) and Pheroprax(R) in the control of the bark beetles (Coleoptera, Scolytidae) in a timber storage yard

The selectivity of the synthetic aggregation pheromones Linoprax(R) and Pheroprax(R) in black flight barrier traps of the Theysohn type was determined by the response of the lineate bark beetle Trypodendron lineatum (Ol.), the eight-toothed spruce bark beetle Ips typographus (L.), and other insects at the timber storage yard of a woodprocessing industry in Ljubljana, Slovenia. The information obtained can be used in establishing a pheromone-based mass-trapping program for bark beetles in the timber storage yard. A total of 24 349 insects were captured in Linoprax baited traps, 78.5% of them belonged to T. lineatum, 19.9% to I. typographus while 1.6% of them were other insects. A total of 22 815 insects were caught on traps baited with Pheroprax, 92.8% of them were I. typographus, 5.8% of them belonged to T. lineatum and 1.4% were represented by other insects. On the control unbaited traps, 3 429 beetles were caught, 52.5% of them belonged to I. typographus, 38.4% were T. lineatum and 10.1% were other insects. Spatial and temporal distribution patterns for T. lineatum and I. typographus were identified. The air temperature and the locations of the Theysohn traps affected the catch. The ecological meaning of selectivity of synthetic pheromones is discussed.