On a warm afternoon in 1971, Shepard and Linnette Erhart spread a cloth under some pines on the Maine coast and prepared to enjoy a summer picnic. "Look," said Linnette, pointing to the turbulent waves below. "Isn't that what we had for breakfast?" Twisting and curling in the Atlantic swells were long, dark streamers of seaweed, identical to the packaged, imported variety that they had boiled up that morning as part of a miso soup.

The Erharts, then as now on a macrobiotic diet, carried a basketful of the stuff home to their farm in Franklin, Maine, and promptly cooked up their first batch of Atlantic alaria. Yum! In the 17 years since, Shepard has hauled tons of seaweed, first to supply friends and then a growing number of natural-food advocates. He also founded Maine Coast Sea Vegetables, the first and now the largest (annual gross: $250,000) U.S. company to sell whole seaweeds as food. This summer, with help from three employees and 20 independent gatherers, he will harvest and dry 10 tons of native alaria, dulse, kelp and nori for packaging into small, handy two-ounce and three-ounce bags. Coming this fall: Sea Chips. Eat 'em straight from the sack.

"The most popular seaweed is dulse," he says. "When it's fried, it's crisp and crunchy and salty." Erhart, 46, claims that seaweed contains only a small amount of sodium, making it especially attractive "to those who crave a salty taste but don't want a lot of salt." These veggies from the briny are high in protein, says Erhart, who enjoys a summer salad of alaria marinated in lemon juice and chick-peas cooked with kelp. The only downside of seaweed, he says, is the harvesting, which is done at low tide and often within a wave-lick of pounding surf. "You never turn your back," he says. "The nightmare is to lose your footing and get carried out."

A Yale graduate and great-grandson of the co-founder of the Pfizer chemical company, Erhart was studying to become a doctor until he decided to leave New York for Maine. Now he feels challenged. "I want to bring this wonderful resource of the ocean to people who don't know it," he says. "I see seaweed in the croissant at the Holiday Inn breakfast table."