PHENOLOGY OF THE COMMON EARWIG FORFICULA-AURICULARIA L (DERMAPTERA, FORFICULIDAE) IN AN APPLE ORCHARD

Observational data taken over 13 years, on the phenology and the abund ance of the first brood of the common earwig, Forficula auricularia L. , in a Dutch apple orchard were analysed. The results are used to indi cate a fixed sampling moment for this predator. The fourth instar nymp hs emerged between 12 June and 10 July, and the adult stage was reache d between 8 and 30 July. The observed phenology, and the number of ear wigs in shelter traps, correlated well with the temperature sum in day -degrees above a thermal threshold of 6 degrees C, accumulated from 1 January. Maximum numbers of earwigs could be trapped in the trees when the nymphs of the first brood entered the fourth instar, generally be tween 600 and 750 day-degrees.