A survey on abundance and species diversity of willow pests

Different species of willow trees are used in preparation of essences, paper, medical engineering. In watershed management and agriculture they are important as a renewable sources of energy. Unfortunately, these trees are infested with various pests which reduce the plant growth and causing reduction of the quality and quantity of the wood. The aim of this study was to evaluate the prevalence and species diversity of willow pests in West Azerbaijan province, Iran. In this study, five watersheds, Barandoz, Mahabad, Zangmar, Zola and Zab, were selected for sampling from April to September 2015. In each region, 10 trees of Salix alba were selected and from each, 4 branches at the height of 1.5-2 m in four cardinal directions were inspected. Species diversity indices of Simpson, Shannon, Brillouin and Simpson and Shannon evenness indices were calculated. The number of 21 species of pests were identified and the results showed that the most frequent of willow pests was registered in the Zangmar region and the lowest in Zab region, respectively. The highest indices of Simpson, Shannon and Brillouin were 0.87, 3.39 and 3.34 which were observed in Mahabad region. The findings of this research show that the role of willow species, sub-species and climate should be considered as important factors in diversity and distribution of willow pests.