As the EPA extends use of the controversial herbicide for two more years, farmers continue to take sides, and the effects on rural America are snowballing.

John and Lisa Zuhlke used to get along well with their neighbor of 10 years. Before they began raising more than 350 varieties of heirloom vegetables and honey on their five-acre operation in Aurora, South Dakota, two years ago, they maintained an amicable relationship with the soybean grower next door. He would scoop snow from their driveway and road and let them hunt his land for dove geese, says John Zuhlke.

Dicamba—the controversial weed killer—upended their relationship.

In August 2017, the leaves on Zuhlke’s vegetable crops started looking deformed, curling up around the edges, or cupping. “It was weird to me. I’d never seen anything like it,” he says. When he asked his neighbor about it, he was told the neighbor had sprayed Engenia, one of three “low volatility” dicamba products that have been approved to spray on fields of dicamba-resistant soybeans after the seedlings have emerged.