Effectiveness of fenitrothion for area control of ticks Ixodes ricinus (L.).

Susceptibility to fenitrothion in all stages of unfed ticks Ixodes ricinus increases with their age and this fact is reflected in the effectiveness of various dosages of insecticides applied for area control. The following minimum, but fully effective dosages of the dust Metation P-5 and the spray Metation E-50 (both preparations contain fenitrothion) for application in separate seasons have been ascertained: In September and October 1 kg of fenitrothion per ha of treated area ensures complete control of unfed ticks until the winter of current year. In Aril 3 kg of fenitrothion per ha is necessary, if tick control is to be ensured until the appearance of the new generation, i.e. until the end of August. In May the control of unfed ticks is ensured by 1 kg of fenitrothion per ha, in June to August by 0.3 kg per ha is fully efficacious.