What is this critter that was found in a cowpea stem?
This small caterpillar is a lesser cornstalk borer (Elasmopalpus lignosellus)(LCB). LCBs are not commonly found in cowpeas, although they are listed as a host. LCB typically prefers soybeans, peanuts, or corn. Usually, the first symptoms are wilting and plant collapse. Physical symptoms are not noticed until an affected plant is dug up. You will find girdled stems and occasionally, a worm inside the stalk.
The adult moth prefers to lay eggs in dry, sandy soil, which is most likely why they were discovered outside their preferred host. In dry years like this one, commercially available pheromone traps can be used to monitor adult populations and decide when to spray.
This week’s question is from Daniel Lyon, Midlands Fruit and Vegetable Agent.
