Über Möglichkeiten der Prognose und Befallsüberwachung und Über Toleranzgrenzen bei der Integrierten Schädlingsbekämpfung im Obstbau

Summary

For the last several years investigations on the possibilities of forecasting the importance of orchard insects and mites in central and eastern Switzerland have been underway to prevent unnecessary treatments.

Factors are discussed which influence the economic importance of a pest. Some approximate population levels are given which may be used as critical population densities under local conditions. Such density criteria should theoretically take into account all the effects and the by-effects of the insecticide treatment in question and of the possibility of no treatment. Therefore the comparison of different methods of pest control will have to be continued over many years.