The aim of this study was to investigate relationships between diameter and height with bark thickness of Lebanon oak (Quercus libani Oliv.) and effect of geographical aspects on bark thickness. This study was done in Northern Zagros forests, Western Iran. Socio-economic problems as well as lack of information about forest situation are main obstacles for proper management in these forests. One hundred and thirty five sample discs were taken from 45 cut trees. Samples were measured and analyzed with Minitab 14 and SPSS 15. Results from One-way analysis of variance, demonstrated that there is no significant difference in bark thickness in various aspects on trees. In order to indicate a proper model for bark thickness estimation from diameter and height, mean of bark thickness of various aspects, with highest correlation with diameter (R = 0.877) and height (R = 0.74), was entered into model. Quadratic and linear equations have best compatibility to estimation of bark thickness from concerned factors. Mean of bark thickness was measured about 12.6 mm. Results can use in management of these forest in order to determine potential values of forest with consider bark as a non-wood forest product (because of valuable raw materials) and effective factor on sprouting ability of oaks (to make a forest regulation model based on coppice method).
