Significance of tree architecture with regard to windthrows occurred in broadleaved mixed stands in Dobresti Forest District, January 2003

摘要

Wind throws affect stands on steep slopes and shallow soils, mostly treeswith asymmetric crowns, with high height/diameter ratio; however wind throwsoccur relatively seldom in broad-leaved mixed forests as compared to conife-rous stands. Climatic events which induced windthrows and wind breakage atDobresti (Bihor county) in January 2003, such as hard winds and watery snow-falling affected trees with large crowns of Carpinus betulus, Fagus sylvatica,Prunus avium, Quercus petraea, Fraxinus excelsior, Alnus glutinosa. Trees with short, narrow crown remained unaffected or slightly affected. Many of overthrown trees presented rotting symptoms, also fructification ofFomes fomentarius, Stereum hirsutum, Trametes versicolor and insect damage;such an event generates a multitude of infestation and infection sites