Analiza porównawcza stopnia uszkodzenia jesionu wyniosłego (Fraxinus excelsior L.) i olszy czarnej (Alnus glutinosa (L.) Gaertn.), rosnących w zmieszaniu lub bliskim sąsiedztwie

The paper presents a comparative analysis of the degree of damage to common ash and black alder trees growing in mixture or a close neighbourhood. Three variants of the damage assessment method were applied in the analysis: defoliation−based variant I, vitality variant II and synthetic damage indicator−based variant III. It was demonstrated that on average ash stands were more damaged than alder stands. This allowed to put forward a hypothesis that there is an alternative to replace ash with black alder on some, especially wet habitats where the dieback process is largely advanced.