Pest Alert! Western Bean Cutworm Caught in Clark County

July 14, 2008

Today I caught a Western Bean Cutworm (WBCW) moth in my pheromone trap located in East Central Clark County. This is an interesting find due to last year these moths were only caught in Northwest Ohio in very low populations. I did not expect to catch a moth this far south in Ohio, but surprisingly the WBCW moths are moving through Ohio.

The Western Bean Cutworm is native to the western United States, where it was first described as a pest of dry beans and later of corn. Larvae feed on developing corn ears, with damage estimated at 3.7 bu/ acre when a field averages one larva per plant. Because WBC larvae are not cannibalistic, infestations of multiple larvae per ear can occur, increasing damage. Larvae also feed on the ear tip and through husks, creating entry points for plant pathogens and potentially contributing to reduction in grain quality and increasing mycotoxin levels.

Adult WBCWs are about ¾ inches in length, with 1) a distinctive cream-colored stripe along the forewing’s front edge, 2) a lighter colored circular spot just behind and along the stripe, and 3) a boomerang-shaped spot near the end of the stripe. There is one generation in the Midwest, with adults in the western edge of their expansion beginning their flights in late June, and peaking in numbers in mid-to-late July. In order to track the entire moth flight, we will continue monitoring the traps until August 15.

See the WBCW moth in the picture to the right. Note the "eye" spot and "half crescent" located on both wings.