In order to assess the impact of resin exploitation on biometrical indices of Pistacia atlantica , an abandoned stand (mass turpentine had been exploited in the past, but harvesting turpentine had ceased for the last 22 years (1970-2012)) with an area of 4.8 ha and a utilizated stand with an area of 9.6 ha, with similar physiographic conditions were selected in the villages Bivandbala and Bivandpaeen, Javanroud, Kermanshah province. To assess the biometrical indices of the two studied stands, complete series of inventory was performed including the registration of spieces name, and the measuring of dbh for all trees. Moreover, the quantitative characteristics of trees (such as collar diameter, total height, trunk height, and crown diameter) were measured. Normality was evaluated using Kolmogorov–Smirnov test, the distribution of trees in diameter classes was computed using chi- square test and the comparison of biometrical indices was performed by Independent-samples T test. The results showed that the mean of biometrical indices such as total height, crown length, crown area, collar diameter and relation crown area into basal area of Pistacia atlantica were significantly different between the two studied stands. The value of studied quantitative variables was higher in abandoned stand expect collar diameter. the other characteristics (such as trunk height) did not show any statistically significant difference between the two studied stands.
