Northern bark beetle (Eurasian bark beetle) - Ips duplicatus (Sahlb.)From: Kolk A., Starzyk J. R., 1996: The Atlas of Forest Insect Pests Occurrence: The central, northern and eastern Europe, and the southern Siberia. Host plants: In Europe, mainly the Norway spruce, rarely the Scots pine or mountain pine. In Siberia, mainly the larches. Morphology: Beetles are 2.8-4.5 mm long, dark brownish or blackish, similar to Norway spruce beetle. Elytral declivity is smooth shining, with 4 teeth on each site. In male third tooth widened on the top joint with second one at base. Females have all teeth sharp. Biology: Adults overwinter in litter. They are active in April-May and in July-August. This species has one or two generations per year, in dependence on weather conditions. Males construct nuptial chambers and attract 1-5, normally 2-3 females by the aggregative pheromone. Females bore galleries where lay eggs. The pattern of egg and larval galleries is similar to this of the European spruce bark beetle, but smaller. Damage: This species usually occurs together with I. typographus, but infests mainly the upper part of stems in sunny places in stand openings. Strong wind, fire and defoliators are the most important factors leading to outbreak of this beetle. The higher is the abundance of the beetles, the higher is the number of healthy trees attacked. Preventive measures: Cutting and removal of windthrows and weakened trees. Utilization or insecticide spraying of branches and tops in spring and summer time. Control: Cutting and removal of infested trees in the period from April through September. They can be easily recognized by felling down of current year foliage. Fallen trap trees should not be used as they are weakly infested by I. duplicatus.
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Forest Pests: Insects, Diseases & Other Damage Agents |
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