Commercial fields of sweet corn in coastal southern California were sampled for corn earworm,Heliothis zea(Boddie), eggs in 1986 and 1987. Staggered planting schedules within each study site produced fields of varying maturity that overlapped in occurrence. Using stepwise regression, we quantified the dependence of egg density on field size, adult population level as estimated with pheromone traps, and field maturity as estimated by plastochron index. Also included were three variables associated with the probability of female moths finding a more suitable host: the hectares of older corn available, distance to the closest older cornfield, and the mean distance to all older cornfields. We found egg density to be significantly related to field maturity and the distance to the closest older cornfield. In 1987, when the average distance between fields was less than in 1986, egg density was more closely associated with field maturity and, therefore, host suitability. These results are discussed in relation to optimal oviposition theory.