Managing Lygus hesperus in California strawberries with alfalfa trap crops and the parasitoid Peristenus relictus

Trap crop management protocols were evaluated to determine how to best reduce western tarnished plant bug (WTPB) (Lygus hesperus Knight) populations in alfalfa (Medicago sativa L.). The effect of the imported WTPB parasitoid Peristenus relictus (Hymenoptera: Braconidae), which was recently established in Central Coast strawberries and associated alfalfa trap crops, was also studied. Vacuuming, insecticide applications and parasitism all reduced WTPB densities in alfalfa trap crops. Appropriate integration of trap crop management protocols with conservation of this imported biological control agent is important to limiting strawberry damage caused by WTPB in both organic and conventional strawberries.