The 2001 growing season marks the sixth year that Bt corn varieties were grown and evaluated at the Northeast Research and Demonstration Farm. Bacillus thuringiensis, commonly known as Bt, is a naturally occurring soil bacterium toxic to European Corn Borers (ECB) that has been genetically modified and inserted into corn hybrids. Different Bt genes and different promoters, called events, vary in their expression and subsequent level of ECB protection.