The corn rootworm complex is the most destructive insect complex to maize in the United States corn - belt.  Growers currently apply 96 million pounds of insecticide to control the corn rootworm complex.  New transgenic technology is currently being developed that has the potential to greatly reduce the reliance on insecticides.  Transgenic maize that expresses the Cry3Bb protein and confers resistance to members of the corn rootworm complex is one of those new technologies.  We have completed a study that examines larval feeding behavior and where the initial feeding begins on the maize root in order to better understand how these plants deter feeding and provide protection to the root system.  The maize plants are grown in a transparent media that allows full view of feeding behavior and larval movement throughout the maize root system.  Digital photographic microscopy was used to document the feeding and movement of the rootworm larvae.  The treatments were MON863 (transgenic), and its isoline and both were infested with non-diapausing Diabrotica virgifera virgifera LeConte neonate larvae.  A third uninfested treatment was used to gather baseline data on the root weights.  Differences in feeding site initiation and overall behavior differences were observed and documented between the transgenic and the isoline.