With organic fields next door, conventional farms dial up the pesticide use, study finds

Champions of organic farming have long portrayed it as friendlier to humans and the earth. But a new study in a California county found a surprising effect as their acreage grew: Nearby conventional farms applied more pesticides, likely to stay on top of an increased insect threat to their crops, the researchers said.

Ashley Larsen, lead author of the study in this week's journal Science, said understanding what's happening could be important to keeping organic and conventional farmers from hurting each other's operations.

“We expect an increase in organic in the future. How do we make sure this is not causing unintended harm?” asked Larsen, an associate professor at the University of California,