A Leslie model was developed for the population dynamics of corn earworm in soybean. In the model, survival rates are affected by predation, cannibalism, and chemical applications. The developmental transition probabilities in the Leslie model were obtained from experimental cumulative distributions. Corn earworm,Helicoverpa zea(Boddie), influx density is affected by crop growth stage and the attractiveness of the crop to moths. Analytic models for components of survival, for crop development, and for influx of adult moths were parametrized from process-level simulations, supplemented by field and laboratory observations. In these models, components are represented by continuous functions, which are at least piecewise analytic. The resulting Leslie model therefore lends itself more conveniently to study of the qualitative behavior of the system, to the design of sensitivity analyses, to incorporation into decision making and management models, and to study of the effects of parameter uncertainty.