This research project sought evidence that a selective, imported biological control agent can persist in alfalfa trap crops that are managed with tractor-mounted vacuums for key pest control in an organic strawberry system in coastal Central California.

Research showed that the imported insect Peristenus relictus successfully controlled lygus bugs in organic strawberries. This biological control agent thrived even with the use of tractor-mounted vacuums to remove bugs from alfalfa trap crops. Parasitism rates were similar in vacuumed and un-vacuumed areas. P. relictus also used nearby plants like sweet alyssum and California buckwheat as alternative hosts. While proximity to these plants didn’t directly increase biological control in this study, future research using better tracking methods may show a distance effect. Overall, this integrated pest management approach combines vacuuming, biological control, and alternative plant resources for effective lygus bug control.