Knox College's spring EquiKnox Lecture will feature a discussion on the herbicide atrazine and its impact on the environment, especially how it adversely affects frogs. Biologist Tyrone Hayes, a professor at University of California-Berkeley who is known for his research on the subject, will present the lecture at 7 p.m. Wednesday, April 20, in Kresge Recital Hall, Ford Center for the Fine Arts.

The event is free and open to the public.

Hayes will speak about his work and his conflict with Syngenta, an agribusiness company that manufactures atrazine.

He was invited to the Knox campus by Knox Advocates for Recycling and Environmental Sustainability, a campus environmental group also known as KARES. According to KARES, Hayes began researching atrazine in 1997, and when his research revealed unexpected toxicities, he was refused funding for future research.

The EquiKnox Lecture is one of several activities planned at Knox as part of Earth Month. Other events include a 5K run/walk and an Earth Day festival.