The insects controlled depends on the type of "Bt" corn being used.
The Bt corn designed to control corn borers will control southwestern corn borer and European corn borer.
Bt corn designed to control rootworms will control rootworms.
In some cases, the company that developed the Bt corn will list another insect species controlled by Bt corn.
For more information on this or other topics related to corn production, contact your state extension corn specialist or your local extension educator/agent.
The following is the link to the corn extension specialists: state extension corn specialist
