During past few years Slovenian forests were increasingly exposed to seveal natural disasters (wind breakages, rain breankages, windthrows), which could be diretly lined with a number of climate changes, appearing worldwide. At the end of June 2006, Jelovica was affected by huricane windthrow, that caused severe damage on Bled%s forest management area. In the damaged area a study was performed. Pre-dawn water potential of Norway spruce was measured after the damage event in different categories of damaged trees by the Scholander pressure chamber. Three categories of Norway Spurce trees were involved: completely damaged trees, damaged trees with functional root system and also vital, undamaged trees. Water potential measurements were carried out during three consecutive dates (6.9., 28.9. in 16.10.2006). With analysis of variance, diferences between groups were confirmed. With the help of sistematic network, traps Theysohn for the bark beetles were settled. With decline of the pre-dawn water potential value, also increased degree of water stress was confirmed, which was highest in the group of trees with damaged root system. Research did not confirm direct connection between drought stress in conifers and number of bark beetles; most probable reason for such conditions was effective and expedite sanation and lower air temperatures after the storm event.
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