The aim of the study was to investigate the abundance of bark beetle species and their damage in Finland. The bark beetle populations were studied in several areas in Finland, both in sites with known beetle damage and without. Two-meter wide lines were measured in the sample plots, where all trees were studied for bark beetle damage in the stem and the crown of the trees. The abundance of bark beetle species and the beetle damages in 25 study areas, and 52 different species are discussed in detail.
Divided by their lifestyle, the most important groups of bark beetles are the pine shoot beetles (Tomicus sp.), beetles reproducing in Scots pine (Pinus sylvestris L.) stems and branches under the bark, beetles reproducing in Norway spruce (Picea abies (L.) H. Karst.) stems and branches under the bark, beetles living in the other coniferous trees, beetles reproducing in roots, beetles reproducing under the Betula sp. bark, beetles reproducing in other deciduous trees and beetles reproducing inside of the stems. Of individual species, Blastophagus piniperda (now Tomicus piniperda) and B. minor cause worst damage to pine and Ips typographus (L.) and Pityogenes chalcographus (L.) to spruce. Serious damage is caused also by Xyloterus lineatus to coniferous trees, Polygraphus polygraphus and P. subopacus to Norway spruce and Scolytus Ratzburgi to Betula sp.
The PDF includes a summary in German.