The 2014 ice-storm caused severe damage to forests in the Postojna region. In our research, we studied ice-storm damage and growth of various tree species before and after the ice-storm in the forest management unit Unec-Škocjan. We used data from permanent sample plots, measured in 2003, 2013 and 2023. We determined the level of crown damage in three classes for various tree species and its diameter growth as response to damages. On the plots 3143 trees were measured in 2013 and only 2230 trees in 2023. Most of the ‘missing’ trees were harvested or dead spruce trees. Broadleaves were found to be more susceptible to ice-storm damage than conifers, but susceptibility was species-specific. The highest damage rate was found in Scots pine and other noble broadleaves, and fairly high also in beech and sycamore maple. The lowest damage rate was found for silver fir and Douglas-fir. The response of trees to ice-storm damage was also species-specific, with conifers exhibiting better diameter growth. The highest average diameter increment in the period 2013-2023 was observed in Douglas-fir and silver fir, while it was smaller in broadleaved trees. The level of crown damage had a significant influence on diameter growth. As damage level increased, growth decreased continuously for most species, the exceptions being silver fir and Douglas-fir. A comparison of diameter growth between tree species before and after the ice-storm showed that damage had more negative impact on growth of broadleaves than conifers. Based on the results, we can recommend that even heavily damaged silver fir trees can be left in stands, as the mortality rate of damaged silver firs was low, and they responded exceptionally, exhibiting high growth rates. Douglas-fir may represent a potential replacement species of conifers as it is resistant to ice-storm damage and grows well.
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