Hemerobius pacificus oviposition closely followed the population densities of Myzus persicae which peaked in late fall and declined to zero in spring in an untreated artichoke field. A second peak of oviposition by the predator followed the increasing populations of the artichoke plume moth (=APM), Platyptilia carduidactyla in spring. Where Hemerobius eggs were released, the aphid populations were reduced consistently, while the APM damage was reduced only at larval infestation levels of APM above 10%. Oviposition by wild Hemerobius was lower in plots where aphids had been reduced by released predators. APM infestations were estimated to be lowered by 30% by wild Hemerobius populations, while hymenopterous parasites accounted for 14% of the larval mortality of APM. Protein + sugar food sprays applied 5 times during the year slightly increased Hemerobius oviposition which in turn led to lower aphid populations and slightly reduced APM infestations. Hemerobius, the only common active predator in artichokes during winter, is considered an important control agent of aphids under cool conditions, and is a mortality factor of APM larvae. Hemerobius should be preserved in integrated control program
