After the severe ice storm of 2014 a high number of damaged trees were not removed from forests. Due to lack of general knowledge about processes occurring in damaged trees, a study involving 14 European beech and 12 Norway spruce trees was conducted in Arboretum Volčji Potok. Trees were categorized by crown injury; injury class K % undamaged, A % damaged less than 50 %, B % damaged between 50 and 75 % or C % damaged more than 75 %. During the 2014 growth season microcores were collected every fortnight using a Trephor tool. Changes in crowns were also observed and noted. Transverse sections of microcores were prepared and observed using light microscopy and a picture analysis system. Crown injury had no effect on leaf unfolding date in beech and young sprouts occurrence in spruce. Success of crown restoration in beech differed from tree to tree regardless of severity of crown injury. No crown restoration was seen in spruce. On average, xylem rings were 20 to 95 % narrower in damaged beech trees and 35 % narrower in damaged spruce trees compared to the undamaged trees. Damaged trees also produced narrower phloem rings. In damaged beech trees xylogenesis started and finished sooner than in undamaged ones. On the other hand xylogenesis started later and finished sooner in damaged spruce trees compared to the undamaged ones. The biggest differences in cambial activity in beech appeared between class A and class B, and in spruce between class K and class A.
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