CHRYSOPERLA PLORABUNDA (NEUROPTERA: CHRYSOPIDAE) LARVAE FEED DISPROPORTIONATELY ON THRIPS (THYSANOPTERA: THRIPIDAE) IN THE FIELD

Green lacewings (Neuroptera: Chrysopidae) are commercially available augmentative biological control agents. Despite centuries of recognition as beneficial insects (Darwin 1800), scant information can be found describing what lacewing larvae prey upon in the field when several different prey species are present (New 1975). I assessed the types of prey that Chrysoperla plorabunda (Fitch) larvae consume when they are released on peas, Pisum sativum L. (Fabaceae), in western Washington. In 1997, two field assistants and I made observations at three sites: the Rent's Due Ranch (RDR: 48°14′N, 122°22′W), an organic farm located just outside Stanwood, Washington, and two research farms (Sumner: 47°11′N, 122°13′W; and Fife: 47°12′N, 122°20′W) in the Washington State University extension station system. Planting dates differed among these sites; at RDR, peas were planted in the spring, whereas we planted peas at the Sumner and Fife farms in June and July, respectively. Despite this and other differences, the peas at each site harbor similar insect communities (unpublished data).