Swiss stone pine dieback in the Tatra Mts. – assessment of intensity and impact of cambiophagous insects

The strictly protected Swiss stone pine (Pinus cembra) is one of the most valuable elements of Polish dendroflora, naturally distributed only in the Tatra Mts. (S Poland/N Slovakia). In 2008−2009 intense P. cembra dieback was recorded in Slovak part of the mountains, especially in the localities adjacent to the Norway spruce stands affected by bark beetle Ips typographus outbreak. The mortality of individual P. cembra trees was observed in 2012 also in the Polish part, next to the area of the bark beetle outbreak on spruce. In the winter 2017/2018 the survey was carried out in order to assess the intensity of P. cembra dieback and the impact of the bark and wood boring insects on this process. In Suchej Wody Valley, where all P. cembra trees were precisely mapped in 2004−2008, health status of all previously living trees were checked again. In the summer 2018 bark samples from 50 dying or dead standing trees attacked by those insects and distributed over the whole Tatra National Park area were collected in order to define their species composition based on the gallery systems and (if possible) beetles or their fragments. Only 4 out of 439 checked trees (