The Cornell team said the risks to monarchs could be heightened because the butterflies migrate northward through the U.S. Corn Belt from their winter homes in Mexico during the spring months, when corn pollen is thickest.

CNN: Researchers find bio-engineered corn harms butterflies

Cornell's laboratory research suggests that wind-blown pollen from the Bt corn could disrupt the monarch caterpillar's feeding -- often killing them before they metamorphose from caterpillars to butterflies.

CNN: Researchers find bio-engineered corn harms butterflies

This sterile desert has nothing to offer -- except perhaps a tiny bit of the thousands of tons of agricultural pesticide applied to the corn, way back at planting time, that makes its way to the pollen collected by the bees, which is stored and eaten later.

CNN: What's killing the bees