Abstract
In this paper a process-oriented model of spruce budworm phenology is developed which produces simulations comparing favorably with observed phenological trends taken from literature. Major features of this model include: (1) non-linear descriptions of temperature-dependent development of larval instars and pupal stadium; (2) three sources of variability in development rates (intrinsic, sex-related, and microclimatic); and (3) generation of daily temperature cycles for four microhabitats from input min-max air temperature data.