Up and coming pest in nurseries: Update on red-headed flea beetle biology and management

Systena frontalis Fabricius (Coleoptera: Chrysomelidae), commonly referred to as red-headed flea beetle, has become a major defoliator of containerized ornamentals in eastern U.S. nurseries, with grower surveys indicating insecticide applications of pyrethroids and neonicotinoids up to twice weekly during peak activity. In Virginia, phenology shows three main adult activity peaks (late June, late July, and late August into early September) with precise timing of emergence and feeding varying by region. In mark-recapture trials using fluorescent powder, adults dispersed as far as 30 m from the release point within 48 h, underscoring rapid recolonization and the limited spatial efficacy of hot-spot treatments. Laboratory bioassays assessed bifenthrin, lambda-cyhalothrin, imidacloprid and alternative active ingredients against adults and larvae; where several alternatives proved as efficacious or more than bifenthrin, supporting their inclusion in rotational programs. We also compared overhead and micro-irrigation regimes on Hydrangea paniculata and found that overhead watering reduced foliar residues by up to 70% within 24 h, whereas micro-irrigation directed to the substrate maintained effective insecticide deposits for five days, informing recommendations to synchronize spray applications with irrigation events. To advance sustainable IPM, we propose combining: 1) systemic drenches or granular insecticides to control larvae in the pots, 2) foliar applications of non-pyrethroid insecticides during the peaks of activity, and 3) physical separation of new and established plantings to restrict adult movement. These measures offer a biologically informed framework to reduce reliance on broad-spectrum insecticides, lower production costs, and enhance environmental stewardship in S. frontalis management.