Phenology and Management of the Obliquebanded Leafroller (Lepidoptera: Tortricidae) in Apple Orchards

Abstract

To manage properly the obliquebanded leafroller, Choristoneura rosaceana (Harris), its phenology must be understood in quantitative terms. We measured the development and activity of all of its life stages in the laboratory, insectary, and orchard. Some of these data were used to create a simple phenological model, which was simulated to produce a frequency distribution of hatching times for the summer generation. Separate data sets were used to validate the model. We tested two insecticide-treatment times suggested by this frequency distribution in commercial orchards. Results indicated that a management policy requiring one application is both sufficient and robust with respect to physiological time, although an application 400 degree-days (base 6.0°C) after the beginning of male moth flight may be safer than an earlier time.