FRESNO — Farmers in "America's Salad Bowl" are turning into hunters -- stalking wild pigs, rabbits and deer -- to keep E. coli and other harmful bacteria out of their fields.
It's part of an intense effort to prevent another disaster like the 2006 spinach contamination that killed three people, sickened 200 and cost the industry $80 million in lost sales.
The exact source of the contamination was never discovered, but scientists suspect that cattle, feral pigs or other wildlife may have spread the E. coli by defecating near crops.
The pressure to safeguard crops comes from the companies that buy fresh greens. In response, some farmers are learning how to shoot animals that could carry the bacteria. Others are uprooting native trees and plants and erecting fences to make their land inhospitable to wildlife.
Spinach grower Bob Martin has even poisoned ponds with copper sulfate to kill frogs.
But some officials have questioned whether such drastic measures are necessary based on limited evidence.
"We're trying to talk now with the companies, buyers, retailers, wholesalers to bring things back into balance," said Scott Horsfall, executive director of the Leafy Greens Handlers Marketing Board, which oversees farming standards drawn up after the 2006 E. coli contamination.
Concern over contamination is most pronounced in the Salinas River Valley. The lush valley, nicknamed America's Salad Bowl, grows 60% of the nation's lettuce.
The nonprofit Resource Conservation District of Monterey County surveyed 181 leafy-greens growers who manage more than 140,000 acres. The survey showed that more than 30,000 acres had been affected by trapping, poisoning, fencing or removal of habitat.
Growers, packers and shippers adopted new food-safety standards last year for farms, including requiring 30-foot buffer zones between fields and grazing land for cattle, which are known carriers of E. coli.
The standards acknowledged that wildlife could also carry the bacteria, but they imposed no requirement for buffers between wildlife habitat and fields.
"I think there's a little brinksmanship going on," said Hank Giclas of Western Growers, who was part of the committee that wrote the standards. He worries that processors are exceeding the rules to gain a sales advantage without good science.
Industry representatives defend their above-and-beyond restrictions.
Barbara Hines, a spokeswoman for Fresh Express, which processes 40 million pounds of salad each month, said the company's tighter regulations were "generally valued" by its retail customers, which include grocers such as Safeway and Vons
Said Terry Palmisano, a senior wildlife biologist at the California Department of Fish and Game: "We have two extraordinary resources in this area: wildlife and our agricultural community. It's our position that you don't need to destroy one in order to save the other."