Mole crickets are one of the most destructive groups of turf and pasture pests. The damage they cause annually is high. For best timing of application of chemical insecticides, it is necessary to determine the time of egg hatching and peak of population density of first and second nymphal instars. Bioecology of mole crickets and seasonal population dynamics in 2004-2005 were studied at two sites in Isfahan, which were Zayandehrood riverside and Mirzakochakkhan parks. Samples were randomly collected within damaged areas by soil flushing by 4 liters of 0.4% aqueous solution of dishwashing soap into a 0.25 m2 area of turf. Mid-line pronotal length of collected nymphs was measured to separate the nymphs into size X – 0.38 and Y= 0.41 X – 0.441 are suggested for Zayandehrood riverside and Mirzakochakkhan parks, respectively. Insecticides used included Chlorpyrifos spray 0.15 %, Fenpropathrin spray 0.07 % (16 lit/m) and Carbaryl 5% bait (200 kg/ha) in the field indicated that the mortality was high ( 90%) and they were not significantly different from each other. In the laboratory, Chlorpyrifos caused significantly higher mortality than other two insecticides (P 0.05). The results of baits, Chlorpyrifos 2%, Fenpropathrin 1.5% and Carbaryl 4% used in a controlled field trial showed that Chlorpyrifos with 84% mortality (on surface and subsurface) (P 0.05) was significantly different and Chlorpyrifos bait was the most effective
