(AP) -- The No. 2 official at the Agriculture Department recently got a real-life lesson in the loose definition of the trendiest word in groceries: "local."
Walking into her neighborhood grocery store in Washington, Kathleen Merrigan saw a beautiful display of plump strawberries and a sign that said they were local produce. But the package itself said they were grown in California, well over 2,000 miles away.
The popularity of locally grown food - which many assume means the food is fresher, made with fewer chemicals and grown by smaller, less corporate farms - has led to an explosion in the use of the word "local" in food marketing. It's the latest big thing after the surge in food marketed as "organic," another subject of continuing labeling controversy.
But what does local mean? Lacking common agreement, sellers capitalizing on the trend occasionally try to fudge the largely unregulated term. Some grocery stores may define local as within a large group of states, while consumers might think it means right in their hometown.
"It's a sales gimmick," says Allen Swann, a Maryland farmer who became frustrated when he realized a nearby grocery chain was selling peaches and corn from New York and New Jersey as local produce. "They are using the word local because of the economic advantage of using the word local."
A federal definition is unlikely because of the diversity of crops and growing regions around the country. A set distance or definition that works for one state or one crop may not make sense for others. But some states have taken a crack at it.
Vermont defines "local" as grown within the state or within 30 miles of where it is sold. Massachusetts has similar restrictions for the word "native." And numerous other states have made it easier for local farmers to advertise that their food was produced in-state.
Maryland recently proposed a new rule that would require retailers to disclose what state a food is from if they advertise it as locally grown. Maryland Agriculture Secretary Earl "Buddy" Hance says the state settled on that approach so consumers could be the ones to decide what they think is local.
"We were concerned that when a consumer went into a store and saw that they were buying 'local' corn they thought they were supporting Maryland farmers, and that wasn't always the case," he says.
The U.S. Agriculture Department has found that there is no generally accepted definition of local food. With few regulations, retailers have different standards.
Whole Foods Market says a food cannot be labeled as local unless it traveled to the store in seven or fewer hours by car or truck. Wal-Mart labels produce as local if it is from the same state where it is sold. Supervalu, which operates some Albertsons stores, Jewel-Osco and other supermarket chains, defines local as within regions that can encompass four or five states. Safeway defines local as coming from the same state or a one-day drive from field to store. Many retailers just leave it up to individual store managers.
The Agriculture Department says consumer preferences for locally grown food can mean more jobs and profits for local farmers and higher produce sales in stores. The department estimates that locally grown foods will generate $7 billion in sales this year, up from $5 billion in 2007.
The department's Merrigan says the local movement has bigger challenges than labeling, such as bringing enough infrastructure to rural areas and widening distribution networks as consumers demand more locally grown food.
And they will continue to demand it, says Melissa Abbott, director of culinary insights at The Hartman Group, a Seattle-based consumer research group. She says the company's surveys show that consumer preferences for local foods have surmounted preferences for organic foods, and they will want food grown closer and closer to home as the trend continues.
"The idea of local is very beautiful to people," she says. "In the consumer's mind it represents a simpler, more gentler time."
Restaurants are also hoping to capitalize on the local trend. Chipotle gets some romaine lettuce, peppers, onions, oregano and tomatoes from local farms. The restaurant chain defines local as coming from within about 250 miles of one of the chain's 20 distribution centers.
Dan Barber, the chef of New York City's Blue Hill restaurant, grows much of his own food at a farm outside the city. He says he considers food grown within 150 miles as local. But that definition may not work for everyone, he said.
"What's local in New York could be very different from what's local in North Dakota," he says. "It all depends on what's available. The question really should be, are you taking advantage of your region's natural ecology?"
The produce and retail industries see tremendous opportunities in the trend. Ray Gilmer of the United Fresh Produce Association says the local label is generating the same enthusiasm as the organic movement, because consumers are learning more about what they buy.
Many stores have rearranged their purchasing and distribution networks to buy food closer to home. Others who can't bring in local produce will instead post a picture of the farmer or the name of the farm to help consumers feel more connected, Gilmer said.
"You can tell a story associated with a tomato, and that's a new conversation with the consumer," he says. "Players big and small are trying to figure out how to do that."
Merrigan says consumers will have to "be smart and ask tough questions" to make sure they are really getting local foods.
"It requires consumers to help police this and for retailers to be honest brokers if this is all going to work out," she says. "And we want it to work out."
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