Wood anatomy of ivy-hosting black alder (Alnus glutinosa Gaertn.)

Abstract: Thestudyaimsatinvestigatingtheimpactofivy( Hederahelix L.)onthegrowthandonsomewoodanatomical characteristics of black alder trees. Ivy-hosting and non-hosting black alder have a similar woodanatomy in terms of qualitative properties. However, in ivy-hosting trees tangential and radial diameter ofvessels are narrower (p <0.001), and inter-vessel pits are smaller (p <0.01), whereas vessel frequency ishigher(p<0.05)thanthoseofnon-hostingones.Theaveragemaximumrayheightisgreater(p<0.05),andray number mm -1 is lower (p < 0.001) than those of non-hostingindividuals.In addition,the last ten years’average radial growth has decreased 39.5% compared to that of non-hosting black alder. Additionalkeywords: ivy impact, host tree, secondary xylem Address: BartinUniversity,FacultyofForestry,DepartmentofForestBotany,74100,Bartin,Turkey,e-mail:yamanbar@gmail.com Introduction Hederahelix L.,commonlycalledasEnglishivy,isawoody species climbing to vertical surfaces such assuitable trees, cliffs, and walls (Chamberlain 1972;Metcalfe 2005). It is an aggressive plant competingwithgrasses,herbsandtreesinitshabitat(Morisawa1999; Okerman 2000), and actually smothers mostseedlings, breaks host tree’s branches, and acceler-ates tree death (Wyman 1969). It can impact the for-est floor, the shrub layer and the canopy of a forest(Simon2004).Therefore,itisconsidered