Modified summer programme using border sprays for managing codling moth, Cydia pomonella (L) and apple maggot, Rhagoletis pomonella (Walsh) in Ontario apple orchards

The efficacy of two insecticide control programmes for managing codling moth, Cydia pomonella, and apple maggot, Rhagoletis pomonella, were compared in commercial apple orchards in Norfolk County, Ontario, Canada, during the 1993 and 1994 growing seasons. In the cover spray programme, sprays of organophosphorous (OP) insecticide for codling moth and apple maggot control were applied to the entire orchard following Ontario integrated pest management guidelines for apple. In the border spray programme, an initial cover spray of OP insecticide was applied to the entire orchard to eradicate any codling moths that had colonized the orchard during the previous growing season, and subsequent sprays were applied only to a c. four-tree-wide (i.e. c. 20 m) zone around the perimeter of the orchard. The border sprays were applied to control codling moths or apple maggots that invaded the orchard since application of the initial cover spray. The border spray programme provided control of codling moth and apple maggot similar to that obtained using the cover spray programme with no significant increase in other pest damage. One benefit of using the border spray programme would be a reduction in the cost of controlling codling moth and apple maggot. Another benefit of using this programme might be an increase in the natural control of other orchard pests like leafminers, aphids and mites. A border spray programme should only be used in orchards where codling moth and apple maggot have previously been reduced to non-detectable levels and border sprays should be replaced with cover sprays when fruit infested with either of these pests is detected during routine monitoring in the orchard. Copyright (C) 1996 Elsevier Science Ltd.