Froggatt's apple leafhopper - action thresholds

There are currently only tentative thresholds developed for commercial use in the IFP programme and these are based on monitoring the levels of leafhopper nymphs on the leaves of each cultivar block. The preliminary thresholds for carbaryl application are:

It is probable that these thresholds will be adjusted in future. Early studies showed that population densities of 31 nymphs/100 leaves in the first generation and 56 nymphs/100 leaves in the second generation did not cause economic damage. However, further research is needed to provide more definitive action thresholds.