The research analyzed the structure of harvested timber in the Bovec region in the period 1995–2020 with an emphasis on sanitary felling due to windthrow, bark beetles and ash dieback. Research also determined the main influencing factors affecting the probability of windthrow and bark beetle outbreaks. Data on the amount and structure of felling were obtained for the research area in the period 1995–2020, as well as data on 26 locations of windthrow with a known time of occurrence and 26 areas damaged by bark beetles. Data were analyzed using descriptive statistics, bivariate analyses and the binary logistic regression. In the research area, significant increase in the amount of sanitary felling after 2018 was detected. The main causes of sanitary felling were windthrow and bark beetle outbreaks, while ash dieback contributed only a smaller share. Binary logistic regression highlighted stoniness, the presence of past disturbances and undulating relief as key factors for the occurrence of windthrow. Bivariate analyses showed that windthrow mainly occurs on moderate to steep ridges with southern exposure, in mature stands with a high growing stock, dense or partly-opened canopy cover, and higher proportion of regeneration stages. Analysis also proved the impact of strong south-western winds. For the occurrence of bark beetle outbreaks, the binary logistic regression highlighted growing stock and share of conifers as key influential factors. Bivariate analyses indicated that bark beetles occurred more frequently in areas with undulating relief, south-eastern exposure, higher proportion of regeneration and stands under regeneration, and a lower proportion of pole stands.
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