Joanne Whalen, Extension IPM Specialist; jwhalen@udel.edu
We recently received verification by a USDA identifier that the moths we sent off for identification we collected in our 2011 survey were Western Bean Cutworm (WBC). The counts were extremely low and no damage was observed to corn ears but this is a pest we will need to watch for in field corn and sweet corn. Adult moths fly in mid-summer and females lay eggs on the upper surfaces of corn leaves. Unlike Black cutworm that feeds on seedling stage corn, this is a later season corn pest, which feeds on tassels, silks, and developing kernels and can cause severe damage. Factors that contribute to the risk of potential problems include: (a) sandy soils, (b) a high percentage of acres in reduced and no-till production, (c) high humidity, and (d) presence of multiple host crops. Since these conditions fit Delaware, we will need to watch and see if this insect becomes a serious pest over the next couple of years.
The following is a link to pictures of the moth, larvae and damage to corn as well as potential management options. http://ipmnews.msu.edu/fieldcrop/fieldcrop/tabid/56/articleType/ArticleView/articleId/3195/Western-bean-cutworm-control-considerations-for-2011.aspx