The 130 or so dairy cows that marched through the Williams brothers' milking barn yesterday afternoon were thinner and slower than usual. The worst drought in more than half a century was taking its toll.

The yearlong dry spell means that each cow gives 10 fewer pounds of milk a day, amounting to $5,000 less each month for the 70-year-old Loudoun County farm. A few have even died unexpectedly, apparent victims of the heat.

The dangerous lack of rainfall also has slashed the amount of hay available for farm animals in Loudoun and throughout the mid-Atlantic, making it even more expensive to keep a herd alive. Corn, soybeans and other crops wither while farm wells are drying up.

If it keeps up much longer, the Williams brothers and other farmers say, they may just have to sell everything and walk away. Some already have.

"The feeding costs haven't gone down," said Donald Williams, 55, chewing on a cigar as he thrust a mechanical milker onto one of his cows. "The labor costs haven't gone down. That money's got to come from somewhere, and that means our pockets. It takes a real bite after a while."

As most Washington residents and suburbanites fret about their dry lawns and dirty cars, those in the countryside whose livelihoods depend on moist, fertile land are beginning to wonder whether they will make it through the year.

Agriculture Secretary Dan Glickman has declared West Virginia and all bordering counties in Maryland and Virginia disaster areas because of the prolonged heat and drought. Yesterday, Virginia Gov. James S. Gilmore III (R) asked federal agriculture officials to designate three more Virginia counties -- Warren, Louisa and Montgomery -- as disaster areas, following a similar request Monday by Maryland Gov. Parris N. Glendening (D) to add 14 counties to that state's disaster list.

"The drought is laying a heavy hand on the state," said Roy Seward, spokesman for the Virginia Department of Agriculture and Consumer Services.

Apples, corn, hay, peaches, soybeans, wheat and pine trees were among the hardest hit crops in Virginia. If dry weather persists, farmers statewide face an estimated $343.7 million in crop losses, according to USDA spokesman Matt Kilbourne.

In Maryland, more than half of the crops are lost already, and farmers in Frederick County are reporting losses of as much as 90 percent. In Southern Maryland, the drought has taken its toll on corn and soybeans -- the main crops in the region -- but it also has caused tobacco plants to wilt in the heat.

Tobacco plants weather droughts well, and rebound when rains finally come. But a continuing dry spell is likely to affect the quality of leaves, meaning poor prices at the market.

"I have some plants that are scorched, and those are a loss," said Betty Russell, who farms 200 acres of vegetables, tobacco, corn and rye in Clements in St. Mary's County.

Russell irrigated part of her 22 acres of tobacco fields with water from a pond. But the ponds, too, are drying up, farmers said.

Maryland's Emergency Board met yesterday to finalize inclusion of the entire state in the drought disaster area, said Connie Byler-Hsu, program specialist for the U.S. Department of Agriculture Farm Service Agency's Maryland office in Columbia. Byler-Hsu said the declaration will make available emergency loans to farmers across the state affected by the drought.

But, she said, "there is help for farmers who are hurting now, without the disaster declaration," such as other types of loans and federal farm subsidies.

In Virginia, agricultural extension agents and USDA workers are preparing damage assessments for 21 counties and hope to have some completed as early as this week. Don Davis, executive director of Virginia's USDA Farm Service Agency, said Shenandoah, Page and Rockingham counties are among the hardest hit statewide.

"It's the most severe disaster we've ever had in that area of Virginia," Davis said. "We have pastures where you could strike a match and it would burn."

Still, despite the damage being done, many farmers in the region don't plan to apply for the emergency, low-interest loans offered by the federal government as part of its disaster relief effort. Most are jittery at forecasts of continued dry conditions through next year, worrying that taking on more debt now -- even at low rates -- will only spell more trouble in the end.

"Why do that? You're just going in the hole," said Moke Anderson, 66, who has been a farmer in Loudoun for most of his adult life. "If it's dry next year, then what? Before long, you're losing the farm and the house and everything else. That's not a real solution."

For Anderson and many others, the solution may be to sell their herds in order to cut their losses.

At Wheatland Farms, where Anderson works, the land yielded half as much hay as usual, and the relentlessly dry summer means no later cutting in most places. At the same time, Anderson and others are feeding more hay than usual to their cattle because they can't graze in parched pastures. The vicious cycle will come to a head this fall and winter.

"We're probably going to have to sell the cows," said Al Burgess, 59, who manages Wheatland. "Otherwise we'll run out of feed, if we don't run out of water first."

In Chaptico in St. Mary's County, farmer Luther Wolfe is losing 300 acres of corn and 300 acres of soybeans to the lack of rain.

Wolfe said the disaster declaration is likely to help many farmers, but he doesn't plan to apply for low-interest emergency loans. "It's made me as contrary as can be," Wolfe joked. "That's what my wife says."

But Mike Russell, who farms 800 acres in Clements, said he plans to take advantage of the emergency loans, and hopes for emergency farm subsidies as well. Russell said he's losing 60 percent of his corn and soybean crops to drought. He did manage to salvage his 40 acres of tobacco with irrigation water from his ponds.

"Running any business is stressful, and when you have to depend on weather, it's even more stressful," said Russell, who has been farming for 22 years. "I'm relying on past years' savings to stay in business. Without farm subsidies, I'd be out of business."

The drought could have an additional impact in Loudoun, a rapidly developing fringe suburb that ranks as one of the fastest-growing areas in the country. Many say the extended dry spell only increases the pressure on farmers to sell their land for subdivisions. The four Williams brothers, for example, may soon make way for a wave of tract mansions encroaching on the north side of their land.

"For traditional farms, for corn and cattle guys, this is an extremely serious situation," said Warren Howell, a Loudoun haymaker who has already sold out his entire year's stock.

"This is going to be the straw that breaks a lot of families' backs," Howell said. "They just can't make a living anymore."

Staff writer Maria Glod contributed to this report.