Sampling for Lygus hesperus (Hemiptera: Miridae) in Strawberries

Several suction sampling devices were compared with a beating tray and a whole-plant sample for determining population abundance of Lygus hesperus (Knight) as well as some beneficial predatory arthropods (Geocoris spp., Hemerobius spp., Chrysopa camea (Stephens), Orius tristicolor (White), and spiders) in California strawberry fields. The Allen-vac (A-vac) sampler best approximated the whole-plant sample for L. hesperus and beneficials except spiders. The beating tray provided the most consistent though lower estimates, but could provide a useful estimate of L. hesperus and beneficial arthropod abundance in an integrated pest management monitoring program. The D-vac provided a slightly lower estimate of L. hesperus density than did the A-vac samples or beating-tray samples at a greater cost in sampling time. For each regression of relative technique against the corresponding whole-plant estimate, the intercept was not significantly different from 0. Taylor’s power law was used to develop variance-mean models for each sampling type tested.