Effect of morphological variables, altitude and tree gender on gum production of Pistacia atlantica in Chaharmahal & Bakhtiari Province forests

This research was performed in order to survey quantitative characteristics of Pistacia atlantica trees on gum production in the forests of Chaharmahal & Bakhtiari Province. At the first step, two elevation classes (1200-1600 m and 1600-2000 m) were choosen and trees selected in different DBH classes. Biometric characteristics of wild pistachio trees such as DBH, crown diameter, total height and bole height were used to assess the impact of gum production on wild pistachio trees. The gum was extracted from selected trees separately and weighted. The results showed that the mean of gum production is 571.9 g in each pistachio tree. Also, significant difference at 5% level between the factors of DBH and total height and at 1% level between crowns diameters were seen. The tree gender also showed a significant effect on the amount of gum production, so that the average production of gum in male and female trees were 608.1 and 354.8 g respectively. The results showed that there is no significant difference between amounts of gum production in different bole height.