Wal-Mart, the world's largest retailer, is under attack from the organic farming lobby over plans to hugely increase the amount of organic produce it sells.
The company is trying to build a green reputation and attract more affluent consumers. Earlier this year, it said it would stock new ranges of organic food.
But groups representing organic farmers say "Walmartisation" will undermine the ethos of the movement and push production into industrial farms.
The Cornucopia Institute, representing family farmers, said Wal-Mart was applying the same price pressures to organic producers as to other suppliers. It warned that Wal-Mart was bypassing smaller farmers for more controversial producers. It has already appealed to the US Department of Agriculture (USDA) over techniques used upon one Wal-Mart milk supplier.
Cornucopia has told Wal-Mart's chief executive, Lee Scott, that the company was "grossly miscalculating" its move into organics. "Those buying organic food are comfortable paying the historic premiums because they think that part of their purchase dollar supports a different kind of environmental, animal husbandry, and economic justice ethic," the letter said.
Mark Kastel, a senior farm policy analyst for Cornucopia, said that the sheer scale of Wal-Mart's move into organics would force the company to increase overseas imports.
"Food shipped around the world, burning fossil fuels and undercutting our domestic farmers, does not meet the consumer's traditional definition of what is truly organic," he said.
Wal-Mart said it would abide by the regulations on organic food. A spokesman said: "We believe strongly that USDA standards for organic products must not be compromised. Our customers who buy organic products expect them to meet these standards, so we feel they must be maintained."Reuse content