Callahan was born in rural Tennessee, and is no stranger to the farming life. But she started raising sheep herself only nine years ago—after, she says, "I finally figured out what I wanted to do." The only ovine dairy farmer in California today, she now works seven days—and at least 60 hours—a week, lambing and milking, and then making and selling cheese. "And when I'm not doing it," she says, "I'm awake at night thinking about it."

She learned her craft originally by taking classes at Washington State University in Pullman and at Cal Poly in San Luis Obispo, and then visited Italy, where she spent time with cheese producers in Umbria and Tuscany. On the rare occasions when Callahan and her husband, Ed, a gastroenterologist, can manage to take a vacation—always between lambing periods—they usually go back to Italy or to Washington, so that she can learn still more about the cheesemaker's craft.

Her dedication pays off: No less an authority than Julia Child has suggested that Bellwether Farms pecorinos rival the best of Italy, and Callahan is hard-pressed to keep up with the demand for her cheeses—among them smoked pecorino, sheep's-milk ricotta and caciotta, and pecorino pepato (with whole peppercorns).

Callahan also sells 15 to 20 lambs a week for meat, and top restaurants all over the Bay Area feature both her lamb and her cheese. "I'm successful," she says, "because I've been blessed with a very receptive audience." Her new life may be demanding and financially precarious, she adds, but "I wouldn't want to be doing anything else."

The Tomales Bay region, just north of San Francisco, is a loosely defined area embracing parts of Marin County and the edge of neighboring Sonoma County. Named for a long, narrow finger of water extending inland from the Pacific Ocean, behind Point Reyes National Seashore, into the region known as West Marin, it has proven particularly attractive in recent years to a new population of urban transplants—attracted to the area by both its singular beauty and its strong agricultural traditions. For these transplants are farm-smitten dreamers, drawn to the land and to the idea of working it, growing things on it, enriching at least one corner of the world with the bounty it can yield. And they aren't Sunday farmers or pastoral dilettantes, but people who worked hard in their original occupations, and work even harder now.

Take Warren Weber, for instance. Weber dreamed of becoming a farmer when he was a boy growing up in Connecticut. He even went on to attend the Cornell College of Agriculture in Ithaca, New York. But then he got sidetracked, teaching junior high school Latin and English back in Connecticut for four years. Graduate work in English literature brought him west, to the University of California at Berkeley, where he obtained a Ph.D in 1972. Back then, he says, the academic job market was slow, and farming worked its way back into his consciousness. "I was into growing things," says Weber, "and when a place became available in Bolinas in 1974, I snatched it up."

His neighbors looked askance at him, first for tilling the fields of his 100-acre farm with plough horses instead of tractors, and later for harvesting his lettuces very young (at the request of Alice Waters of Chez Panisse in Berkeley). Today, though, Weber is one of the most respected organic farmers in California.

"Because we're organic," says Weber, "we can farm next to civilization." He points across rows of baby lettuces—red perella, tango, lolla rossa, little gem, red romaine—to a wood-frame elementary school next door. "It's safe for people, and no fertile land is wasted."

He adds that, to him, "the essence of the organic movement is really the revival of the successful small farm." Due to demand for specialty products from restaurants and an ever-growing number of farmers' markets, he says, it is even possible for a grower to eke out a living from a farm of less than five acres—especially with such crops as berries, cherry tomatoes, and specialty lettuces. "Civilization was built by having farms close to the cities they fed," says Weber. "That was the model in the Middle Ages. It's good for the urban consciousness for people to see where their food comes from."

The famed "longhaired" enclave of Bolinas, where Warren Weber farms, may be the closest West Marin agricultural community to San Francisco physically, but it's the farthest away in state of mind. Defiant residents even tear down road signs leading to the place, hoping to keep outsiders away. That hasn't kept agrarian-minded ex-urbanites from its fields and hillsides.

One of the town's more celebrated residents is Sean Thackrey, who is not a farmer but a winemaker. Thackrey moved to Bolinas in 1963, at first working as an editor for a textbook publisher. In 1970, he opened a gallery in San Francisco, exhibiting 19th- and 20th-century European photographs and graphics. He loved wine as much as art, though, and ten years later, still in Bolinas, he launched a specialized one-man winery that now produces several thousand cases of wine a year from old-vine syrah, petite sirah, and mourvedre grapes. He buys the fruit in various parts of California and trucks it home. After creating his wines, he stores some of them in barrels outside, letting the cold ocean winds provide natural refrigeration. He obviously knows what he's doing, since his wines, fancifully named after constellations (Pleiades and Orion are two of them), have won high praise from critics. They tend to be big, dark, and complicated. "They're like small children," Thackrey says. "They aren't always pretty and well behaved."

Another urban transplant is Dennis Dierks, who worked as a commercial artist in San Francisco, and who has been growing exquisite vegetables in the Bolinas area for nearly two decades, selling to Marin County restaurants and farmers' markets. The entire family pitches in, says Kris Dierks. "Whatever needs to get done, we do. It's not like anybody has specific jobs." Even the younger kids get involved: Zeke makes bicycle deliveries of organic leeks, Russian kale, and up to eight varieties of lettuce, while Sierra picks zucchini and helps harvest the farm's Ruby Crescent potatoes.

Frequently shrouded in fog and raked by cold winds off the Pacific, the Tomales Bay region attracted a hardy group of settlers in the mid-19th century—land-hungry East Coasters and, later, European immigrants, who built sheep, cattle, and dairy ranches in the isolated countryside. Even today, the only link between the western reaches of the area and the outside world is a membrane of treacherous roads. During the Gold Rush, in the 1850s, a proud, isolationist identity developed here, even as farms profited by selling beef and dairy products to San Francisco and the boomtowns of the Sierra foothills. Schooners cruised past colonies of seals and pelicans living in the two bays, Tomales and Bolinas, that are the region's most distinctive geographical features, picking up lumber and farm products and dropping off supplies.

Further settlement of the Bolinas area was encouraged in 1927, when 20-by-100-foot lots were offered for $69.50 to each new subscriber to the San Francisco Bulletin. And the population grew yet again in 1937, when the Golden Gate Bridge was built, linking Marin and Sonoma counties more directly to San Francisco. This was both good and bad: Farmers found a faster route to the urban market for their crops, but at the same time, city dwellers began buying up farmland for residential use. The kind of development that was swallowing up the hills around San Francisco Bay appeared to be just around the corner from Tomales Bay, too.

Farmers and ranchers, feeling pressured to sell their property, got some relief with the passage of California's Williamson Act in 1965. This legislation gives substantial state tax breaks to landowners who put their property into agricultural preserves for at least a ten-year period. Then, in 1980, the people of Marin County went a step further. A group of local ranchers and conservationists, led by Ellen Straus, Phyllis Faber, Gary Giacomini, and Ralph Grossi, established a unique preservationist group, the Marin Agricultural Land Trust (MALT). By buying conservation easements on parcels of land—often entire ranches—MALT is able to guarantee that they will be reserved for agricultural purposes, even if they pass from hand to hand.

Ellen Straus is no stranger to breaking new ground. She and her husband and son run the only organic dairy in California, and are in the forefront of an organic farming movement that has found fertile ground in western Marin County. Ellen's husband, Bill, studied agriculture and animal husbandry in California after fleeing Hitler's Germany. One of his first farming jobs took him to Tomales Bay, where, enchanted by the beauty of the area, he bought a dairy farm—not organic—in 1941. Ellen had emigrated from the Netherlands a year earlier. They met in late 1949 and were married four months later.

From the start, as Democratic Party activists and committed conservationists, the Strauses stood out in this land of cautious, conservative farm families. If they appeared to have little in common with their neighbors, though, Ellen Straus discovered that many of them shared her desire to protect the region's farmlands from development. Working with Gary Giacomini, a Marin County supervisor, and Ralph Grossi, a dairy rancher, she helped amass private donations to finance the first of many MALT purchases.

While MALT was to prove successful—more than 25,000 acres are now under its protection—the Strauses found that their dairy business was running into stiff competition from big milk producers in the Central Valley and Southern California. So in 1994, the family, in an effort spearheaded by son Albert, turned the dairy into a certified organic operation—with 230 organically fed cows sharing the fields with great blue herons and snowy egrets—and began selling their milk and butter directly to the consumer.

In order to qualify for organic certification, a dairy farm's grazing fields must be free of pesticides, herbicides, and chemical fertilizers for at least three years, and the cows must spend at least a year on organic diets before commercial production can begin. The law also states that cows may not be treated with genetically engineered hormones to increase milk production. Albert Straus, who has a degree in dairy science, does things the old-fashioned way: He milks the cows three times a day to maximize milk yield and diminish stress on their udders; if they fall sick, he treats them with either aspirin or homeopathic remedies instead of antibiotics.

The Strauses needed help to market their organic products. To that end, Albert hired Sue Conley, former chef and owner of Bette's Oceanview Diner in Berkeley. Bette's baking mixes are in gourmet food stores all over the country, and, encouraged by her success in selling the mixes, Conley had recently gone into food marketing exclusively. The Strauses approached her and asked for her help in positioning their milk, cream, and butter in farmers' markets, specialty food stores, and restaurants. Today, the milk—which old-timers say has the taste and texture of the milk of their youth—has become so popular that when the Strauses miss a day at one of the farmers' markets, there is loud grumbling from loyal customers.

In addition to her efforts for the Strauses, Conley has also formed a new venture, Tomales Bay Foods, both to showcase a wide range of the region's bounty and to function as a marketing and product development agency for local agriculture. Conley does the scouting that the busy farmers don't have time to do, visiting stores and restaurants and helping her clients decide what to cultivate and how to package and sell what they grow.

"The general population benefits from the agrarian urges of these producers," says Conley. "While we are enjoying the fruits of the organic agriculture movement, these farmers are taking care of the land for us and future generations."