DIGITALNA ARHIVA ŠUMARSKOG LISTA
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both flight periods. The differences between the averages of I. sexdentatus captured to pheromone traps in 4 different months, which the capturing was carried out, were tested by one-way analysis of variance (ANOVA). Because the grouped data were used, the relations between trees which were damaged by I. sexdentatus and healthy and aspects and diameter classes were interpreted through Chi-Square test. RESULTS AND DISCUSSION Rezultati I Rasprava Most common use of pheromones, preferred especially in monitoring aggressive forest pests (Bakke, 1991), are the evaluations depending on the number of beetles captured by traps (Suckling and Karg 2000). Mass trapping practices are being used for more than 200 years (Bakke, 1991) and this method is actively used in sustained forestry management practices in Turkey (Özcan et al., 2014). The reaction time given by I. sexdentatus individuals in a population varies. The effectiveness of pheromone traps (McNeil, 1991) and attraction capacity of the beetle to pheromone (Jactel, 1991) are affected by many factors (Bentz, 2006) such as stand attributes, wind direction, traps being hanged near suitable host trees (Safranyik et al., 2004), biology of the beetles, trap distance (Bacca et al., 2006), placement of traps and installation design (McNeil, 1991; Zahradník and Zahradníková, 2015). The ratio of capture of I. sexdentatus adults in traps at the edge and outside of the stand is higher than the traps inside the stand (Akkuzu and Güzel, 2015). Also, the population of beetles and the amount of beetles captured by traps vary by year and location (Özcan et al, 2011). This research, 14556 I. sexdentatus and 608 T. formicarius were totally captured from using the pheromone traps. In the year the study was carried out, the average number of I. sexdentatus captured by the pheromone traps at the end of 19 weeks long monitoring process is 485. 56,99% of these beetles were captured in 10 traps and the average capture amount of these traps are about 2,65 times more than the total number of beetles captured in traps. Özcan et al. (2011) determined that about 60% of the average number of beetles captured by traps are captured in certain number of traps. Pheromone traps are commonly used in monitoring of bark beetles population (Bentz, 2006). These monitoring help in obtaining data which may be utilized in various ways such as determination of flight activities and timing of control programs for target species (Suckling and Karg 2000). In the first controls performed with the traps in 8th of May and last control performed in 8th of September, considerably low capture ratios were recorded compared to other control periods. According to this, it is seen that flight activities of beetles start before 8th of May and continue after 8th of September and ratios being low and starting and ending dates of flight periods of beetles coincide approximately with these times (Figure 2). Although the conditions of the beetles at the time of capturing are unknown (Özcan et al., 2014), average daily temperature values at the time of first flight starting dates are approximately 11 °C, however, there are also days when the daily maximum temperature values are 20 °C and above subsequently. It is expected that the beetles are captured in traps when the temperature conditions are suitable for their flight (Krieger, 1998). In the study explained by Seedre (2005), it is suggested that the first flight of the beetles is |