From the Windsor chairs on the large porch of George Washington's Mount Vernon estate, visitors can gaze past the building's white columns to the green lawn sloping toward the Potomac River. In the distance across the river, densely wooded hills rise above the lapping water. Not visible in those hills are the homes of families who have lived there for decades, carving out a rural existence and successfully preserving the natural habitat much as it looked to the first president as he sat on his portico. The view across the Potomac from Mount Vernon is Southern Maryland's 4,200-acre Piscataway National Park featuring the National Colonial Farm, a living museum depicting a Southern Maryland tobacco farm on the eve of the American Revolution. Spread across 1,000 acres of the ecologically rich park is the Moyaone Reserve, a private residential community of about 170 families in Prince George's County. The reserve, about 10 miles from the District and near Accokeek, is a throwback to a time gone by, residents said. Narrow dirt roads cut through the reserve, which is filled with green meadows, marshes, ravines, streams, ponds and moss-covered trees. The houses, which are on five-acre lots with hardwoods, hollies, oaks and dogwoods, include 18th century Cape Cod reproductions and contemporary designs. They range in price from about $250,000 to $300,000, said Frances Donohue, a Coldwell Banker real estate agent in Accokeek. Forested lots, where urban noise gives way to the sounds of leaves rustling in the wind and deer and other wildlife feeding on wild vegetation, sell for $125,000 to $150,000 with septic systems included. The lots without septic systems sell for about $50,000. "What I really enjoy are the trees, being close to the river, just the natural aspects of the place," said William Moran, 84, a retired Prince George's County teacher of emotionally disturbed children. "Moving here has been one of the best decisions I ever made." He bought a five-acre lot at Moyaone (pronounced MOY-un) in the early 1960s and built a house on the site in 1969. There's something soothing to the soul when it comes to living within a nature preserve, Moran and other residents said. That's not to say there are no problems. Water well levels have been low as increasing development in neighboring Charles County has tapped into the same underground water supply, Moran said. Snowstorms can make traveling the hilly terrain difficult. Moran quickly noted, though, that the reserve's Moyaone Association keeps the private roads graded and plowed. He said he operated the road grader for many years, drawing on his experience from serving in the Army Corps of Engineers during World War II. Still, whether it's fishing from the public pier at the National Colonial Farm or bird-watching on a warm spring afternoon, there usually is a relaxing element not far from the front doors of residents. Bringing about this mixture of residential community and national park resulted from a joint partnership of the Accokeek Foundation, the Alice Ferguson Foundation, the National Park Service, the Moyaone Association and the Mount Vernon Ladies Association. The Moyaone Reserve, which takes its name from an Indian village on the Potomac shore in the 1600s, traces its modern history to 1923. At that time Washingtonians Henry and Alice Ferguson bought a large tract of land there and built a farm. They later acquired more land and began selling their property in five-acre parcels with a covenant requiring that the parcel of land not be subdivided. When the woodlands near the reserve were placed on the market in 1960, a company proposed construction of an industrial site with oil holding tanks and pumping and trucking facilities. The Mount Vernon Ladies Association, a private group that oversees the maintenance of the Mount Vernon estate, responded by buying the land and forming the Accokeek Foundation to protect the view from the estate. Those two groups then developed the concept of what was to become Piscataway National Park, which stretches seven miles along the Potomac. The effort was aided by Moyaone residents who granted scenic easements to the National Park Service in exchange for tax breaks. The easements place restrictions on cutting trees, commercial development and subdividing lots. "We've been lucky to have so many people here interested in conservation," said Nancy Wagner, a 52-year resident of Moyaone Reserve and the author of a community newsletter called Smoke Signals. "It's amazing, really. There are a lot of strong individualists so it's hard to come to an agreement sometimes, but it all makes for much more interesting meetings." Wagner is the widow of Charles Wagner, an architect who designed about 15 houses in the reserve. Those houses are distinct for their use of large windows for natural lighting, attempting to attain a level of congruence with the wooded landscape. Paul Livingston, president of the Moyaone Association, lives in a contemporary house of cedar, glass and stone, though it's not a Wagner design. Livingston, a computer scientist and engineer, said the drive home through the park feels like a "depressuring" process from the stresses of work. "It's quiet and peaceful," he said. "It's truly a remarkable form of relief." CAPTION: William Moran enjoys the nature preserve's natural attributes and proximity to the Potomac River. ec