Down a dirt road, tucked in rolling fields, John Nutting's farm is a picture of tranquillity. A wintry breeze sighs through the forest. Black-and-white Holsteins chew their cuds in a lazy rhythm. Only the large sign hammered onto a red barn attests to the defiant mood in Maine dairy country: OUR PLEDGE--NO ARTIFICIAL HORMONES.
Hormones are a hot issue in these parts. As do at least 85% of Maine's milk producers, Nutting signs an affidavit each year vowing not to inject his cows with recombinant bovine somatotropin (RBST), a genetically engineered growth hormone. "We're proud of the way we farm," says...