Sustainability of wild pistachio (Pistacia atlantica Desf.) in Zagros forests, Iran

Wild pistachio (Pistacia atlantica Desf.) is the most economically important tree species in many rural areas in the west of Iran. The produces resin used for a wide variety of traditional uses. Because the resin can be harvested non-destructively, the trees are maintained mortality occurs from natural causes. The result is that natural, managed stands include a variety of age classes. In recent years, a lack of size classes has been observed in the Qalajeh forest, which is located in the Zagros Mountain region of western Iran. We established a series of in an area typical of Qalajeh forest to characterize the diameter distribution of the wild pistachio component. We confirmed a deficit of <30 cm dbh, based in the expectation that the landscape-level diameter distribution should be characterized by a negative exponential curve. trees >= 30 cm dbh, de Liocourt's equation closely fit the diameter distribution (r(2) = 0.93), translating to a q-factor of 1.34. We used this curve estimate the deficit number of stems in diameter classes <30 cm. We estimate that this forest should have 19-24 wild pistachio trees/ha in 5-25 cm classes, as compared to about 5 trees/ha found currently. Based on local conditions, we recommend that at least 30 seedlings/ha should planted to allow 6-8 trees to reach to the 5 cm class. (C) 2008 Elsevier B.V. All rights reserved.