Towards Insecticide Free Apple Orchards: Flowering Plants to Attract Beneficial Arthropods

Tanacetum vulgare, Chrysanthemum maximum, Aster tongolensis and Achillea millefolium were planted to attract and retain predacious and parasitoid arthropods in a Quebec apple orchard. The plants covered one-third of the surface of the experimental block and provided nectar, pollen and refuge for beneficial arthropods. The parasitoid fauna increased several-fold during the study. The most important index of pest management in this study was the quality of the fruit at harvest and it attained 90.8% (clean fruit) in the fifth year of the study. The technique cannot be readily adopted into an orchard that is in full production because it would require several years to build up the beneficial arthropod fauna to an effective bio-control force. During that period, pesticides would not be applied and losses in yield would be commercially unacceptable. Habitat management should be used as a template for biological control of orchard pests over which other bio-control techniques can be superimposed to further increase the quality of the yield at harvest.