In beet, spinach, and rhubarb, leaf tissue may be injured. Entry of borers into plant tissue facilitates entry of plant pathogens. The incidence of potato blackleg caused by the bacterium Erwinia carotovora atroseptica , for example, is higher in potato fields with stems heavily infested by corn borers. Direct damage by corn borers to potato vines, however, results in negligible yield loss. Moths can be sampled with blacklight and pheromone traps, and catches by these traps are correlated.
Pheromones attract only males, whereas both sexes are captured in traps with a blacklight.
Blacklight traps tend to be more reliable, but light traps can capture large numbers of other insects, necessitating a great deal of sorting. Pheromone-baited water pan traps seem to be the most efficient method of adult monitoring. Trap catches are usually used to initiate intensive in-field scouting for egg masses, as moth catches are only roughly correlated with density. Techniques other than adult capture can be used to estimate borer phenology. Plant phenology can be used to predict corn borer development.