Relationship between charcoal disease and habitat factors in the Kakasharaf forests of Khorramabad

In recent years, charcoal disease as one of the important causes of oak decline has caused great damages to Zagros forests. Identification of efficient factors in the development of the disease could be helpful in managing strategies. In order to study the effective agents in spreading of charcoal disease in Kakasharaf district forests, which is an infection foci of the disease in Lorestan province, statistically grid in the form of systematic random sampling with dimensions of 200 × 150 m in the GIS software was drawn and applied randomly and trees were assessed on circular plots of 15-are (1500 m2). In the studied area, 9.26 percent of trees were died due to Biscogniauxia mediterranea infection. Result of logistic regression showed that with increase in the values of variables such as soil phosphorus, borer beetles damage, altitude, tree's diameter, percentage of crown dieback and tree's distance from villages, and with decreasing in the amount of crown area, the number of infected trees to charcoal disease were increased. Results of Poisson regression showed that in the final stages of infection to charcoal disease, the values of variables such as borer beetles damage, percentage of crown dieback and tree's distance from villages will be increased.