Seasonal dynamic of radial growth in oak (Quercus castaneifolia C.A. May.) (Case study: Educational and Forest Research of University of Tehran, Nowshahr-Koliak)

The beginning and the ending of radial growth in trees depend on genetics and climatic factors and its intensity varies during a growing season. Studying wood formation dynamics in a growing season will increase our knowledge about xylogenesis of important species and the influencing parameters. For this reason and in order to have a better understanding of a radial growth in oak, four Quercus castaneifolia individual treeswere selected in the research forest of University of Tehran located in the Hyrcanian forest. In 2012, micro-core samples were extracted from trees by Tropher in monthly intervals. Cambial cell divisions and radial growth started approximately on mid-April and terminated at the end of September. The highest number of cambium cell (15-17) and the maximum daily growth rates of all trees were achieved around Mid-June. The results of this research showed that the majority of radial growth in oak occurs from May to mid- July and this fact should be considered in dendroclimatological studies.