Tea green leafhoppers(Empoasca spp.)are considered one of the major pests in tea plantations in Asia.They are however difficult to monitor due to their size and flying and jumping abilities.In this study,we clarified the identification of the leafhopper species encountered in our study plantations,examined the impacts of sampling methods in estimating population abundance and sex ratio,and investigated population dynamics during the life stages from eggs to adulthood.Despite previous reports that Empoasca vitis was the major leafhopper present in our study area,our results showed that only E.onukii was found.Variation in population size and bias in sex ratio was found over time and depending on the sampling methods.In general,adult males were more attracted to yellow sticky cards than females.There were significant differences in population estimates depending on the height and colors of the sticky cards.We demonstrate the importance of understanding the implications of sampling techniques for population estimation and sex ratio bias as well as how temporal variation may affect monitoring results.This study represents the first examining the population ecology of E.onukii in China.