NATURAL BRIDGE, Va.

Virginia Gold is no ordinary orchard. Here, on a spectacular, verdant hill crest south of Lexington, in the shadow of both the Blue Ridge and Allegany Mountains, YoungSuk Estabrook creates new varieties of Asian pears.

In December, the Korean-born Estabrook plans to sell for the first time an oval-shaped, bright orange, crisp and sweet cultivar that she has named Winter Gold, which took more than 10 years for her to hybridize. After harvest, she plans to allow it to sweeten, in cold storage, for one month. Throughout the harvest season, which began in mid-August and continues through fall, 14 kinds of Asian pears are for sale at Virginia Gold Orchard or by mail (see box inside).

Some are sweet. Some are sour. Flavors run from subtle to unexpected. Last season, one variety tasted remarkably like bubble gum. But don't look for Seuri -- the gum-flavored pear -- in the orchard's sales-packing shed. That's where Estabrook gives visitors samples of her work. "It wasn't up to my flavor standards, so I cut it down," she says without a hint of remorse.

The majority of the 4,000 trellis-trained Asian pear trees at Virginia Gold are standardized, time-tested cultivars that were developed in China, Japan or Korea. The exception is "row nine" where Estabrook grows 25 different named varieties for testing and hybridizing.

"We have something special here, something that other farms don't have," says Estabrook on a stroll down row nine where her latest fruits are reaching maturity. "You have to be different to compete with other orchards."

For a moment, forget about pears named Anjou, Comice and Bosc. The Asian pear, Pyrus serotina, also known as the Chinese pear or apple pear, is a different fruit altogether.

All pears, it's believed, have a common parentage from rootstock native to western China. But centuries ago, trees that were taken westward to European countries changed over the years and produced fruit with a texture and flavor like the common Bartlett pear.

Pear stock that made its way eastward across China and eventually to Japan and Korea went on to bear fruit that has more in common with the apple in shape and texture. Unlike their Euro-cousins, Asian pears are consumed when the flesh is firm and crisp. They can weigh anywhere from four ounces to a whopping two pounds or more. Asian pears roughly fall into three groups: round fruits with green to yellow skin, round fruits with bronze-colored mottled skin, and pear-shaped fruit with green skin. The flavor is slightly floral with hints of apple and melon. Chinese railroad laborers in the 1850s brought Asian pear seeds to California, where they have flourished in select groves in the northern part of the state. More than 25 kinds are commercially grown in this country. The best known variety is the round, yellow-skinned 20th Century. Nijisseki is also the most popular pear grown in Japan, where perfect specimens are boxed for gift giving.

In 1976, YoungSuk Jung was working as a secretary in Seoul. She had no interest in orchards but loved a good Asian pear. "For us, they were very special and expensive," she says. Boston-native Paul Estabrook, was working as a field engineer on a hydroelectric project in Korea. That's where he tasted his first Asian pear.

"It was big, sweet and juicy," he says, "not the Bartlett I was brought up on."

In short, they met, married, had two children and eventually settled on a 116-acre farm in New Hampshire, where they planted more than 500 Asian pear trees.

But after a couple of years, they came to realize that a miscalculation had been made. The growing season for Asian pears was too short in New England. They needed to head south.

In 1990, they bought 114 acres in the southern Shenandoah Valley and soon after moved the 500 trees, packed in wet sawdust, to their new home in the foothills. "We will never do that again," says YoungSuk Estabrook with a shake of the head.

All of their original trees subsequently fell victim to bacterial infection and blight. And that's when the couple decided that their ultimate goal was to develop hardy pear varieties that are disease-resistant and best suited to the growing conditions in Virginia. They also set out to create signature pear flavors they could call their own.

Hybridizing or the crossbreeding of plants is all about the blooms -- at least at the start, anyway. Then, it's all about patience.

In Virginia, Asian pears come into flower throughout April, according to the variety. There are hundreds of varieties that grow around the world. A hybrid enthusiast can mix and match at will.

When the flowers open, Estabrook must act quickly. Between 7 a.m. and 8 a.m., before the bees make a move, she uses a fine, camel-hair artist's brush to transfer pollen from the flower of one established variety to another. A plastic bag covers each bloom until the infant fruit forms. Every cross-pollination is logged, by hand, in a notebook with information on the rootstock, disease history and production capabilities. She selects for crossbreeding varieties with dominant genes associated with disease resistance, vigorous growth and good taste.

In late summer and early fall, she gathers the individual fruits from her experimental trees. After sampling them for flavor, she saves the seeds. It's the seeds she's after. Hundreds are planted in rows in a seedling nursery.

Over a period of years, natural selection kills off more than 90 percent of the new saplings. When Estabrook feels the timing is right, the hardiest young trees with the largest leaves are grafted onto established pear stock. After seven more years, the trees bear the all-new fruit. But not all are successful -- sweet and delicious.

For an informal tasting, Estabrook chooses two new, unnamed pears from experimental row nine. Each is washed to remove a clay dust that deters insects.

"I just hope it's not mushy," says Estabrook as she cuts into the first one. Then, "Ummm. Sweet." The second contestant receives an immediate thumbs-down for its small size, dark-brown color and flavor that brings pancake batter to mind. Estabrook says only, "No good."

Paul Estabrook believes that there is an urgency to produce unique pears as soon as possible.

"When we moved here in 1990, one of the key things was that no farmers were even thinking about Asian pears. We've had the market to ourselves," says Estabrook. "But in five years, maybe, lots of other farmers will have Asian pear orchards. We have to be a head above the others."

Estabrook agrees with her husband that the hybridizing will pay off. To that end, the couple has built a new greenhouse for seedlings. But she has some reservations about a future tied to an uncommon fruit.

"If you asked me, I would not do this again. It's too discouraging. A hurricane comes through and all the fruit falls. The birds. The bugs. The disease," she says. "But I am happy to have this wonderful place and have people who appreciate our organic fruit."

YoungSuk Estabrook with a collection of seasonal Asian pears from her Virginia Gold Orchard in Natural Bridge, Va. Above: the Atago variety.