Investigation on the appearance of host trees in woodpecker hunting activity Dendrocopos syriacus (Hemprich & Ehrenberg) on poplar clear wing moth Paranthrene tabaniformis (Rott.)

Poplar trees are among the fast-growing trees and they have a special place in plantation and wood products. Poplar clear wing moth Paranthrene tabaniformis (Rott.) is a major pest of these trees. Each year, in the poplar nurseries, the seedlings of these trees are attacked by this pest, resulting in severe damage to the production of wood and its dependent industries. In this study, normal control of population of these butterflies was evaluated by Dendrocopos syriacus (Hemprich & Ehrenberg) woodpecker. For this purpose, 2217 seedlings from 10 different poplar clones were selected in one of the nurseries at Astaneh-Ashrafieh Poplar Research Station in Guilan province. At the end of the growing season, it became clear all 670 seedlings were infected with galls. In the next step, the activity of woodpeckers and the effect of diameter and height growth characteristics of gall-contaminated seedlings on woodpecker hunting were evaluated by multiple regression analysis and Pearson correlation. The results of this study showed that Syrian Woodpeckers are capable of operating more than 36% on some infected seedlings, and in this regard, the amount of their activity intensifies with the growth of the diameter and height of the seedlings infected with the gall.