What was the controversy about GE corn and Monarch butterflies?
An experiment performed at Cornell University showed that large amounts of pollen from Bt corn applied to milkweed leaves, the natural food of Monarch butterfly larvae, could kill larvae feeding on those leaves. That result suggested that Monarchs might be killed in the environment by consuming pollen from Bt corn plants. EPA had not thoroughly considered that possibility when it approved Bt corn. Subsequent research sponsored by EPA and USDA in several parts of the U.S. and Canada determined that the pollen from about 95% of the Bt corn varieties does not contain enough Bt toxin to significantly harm Monarch larvae. Furthermore, corn sheds pollen for only about two weeks, and for much of the country (except the northern parts of the corn belt) Monarch larvae are not often present when pollen is found on the milkweed leaves. Some questions about possible subtle effects remain unanswered, but it is unlikely that continuing experiments will find significant harm. While some have contende
