The impact and severity of bark beetles in forests is currently increasing on a global scale due to the consequences of climate change. One threat in particular is the introduction and the spread of non-native invasive species.
Among the non-native bark beetle species that have been introduced to Germany, the black stem borer, Xylosandrus germanus, is the one with the greatest potential for invasiveness. Attacking a wide variety of both, coniferous and broadleaf tree species, as well as accepting a wide range of breeding material, the species is already widespread and may evolve into a severe future forest pest. This is of particular importance considering the national forest conversion strategy towards mixed and broadleaf forests and the dominant occurrence of X. germanus on European beech, which is the most abundant broadleaf tree species in Germany.
Since it is considered difficult to control X. germanus using insecticides, and taking into account that their application can have negative effects on non-target species and may be prohibited in protected areas, we have studied the effects of semiochemicals that potentially induce a repellent response of X. germanus, such as anti-aggregation substances and various non-host volatiles, using slot traps in different forest habitats.
Our data suggest that using such semiochemicals can be a successful environmentally friendly strategy in X. germanus management.