Sixpenny Chimney Sweeps in Woodbridge ran advertisements for two weeks, seeking bricklayers, chimney technicians and air duct cleaners. But few applied.

"We usually get more responses," said Lisa Mendoza, a secretary at Sixpenny. "But there's a big demand for bricklayers now, and they all want to work just four or five hours a day, have an hour for lunch, and go home early."

Sixpenny isn't the only company in Northern Virginia bemoaning a scarcity of workers. With unemployment in the region at 2 percent in September -- and an even lower 1.9 percent in Loudoun County -- employees are in big demand.

Yet, many of the jobs being created are lower-paying ones in retail and services that cater to the burgeoning population in Washington's outer suburbs. Even with the unemployment rate so low, applications for food stamps are growing at a faster rate than the population. Some social services officials attribute the rise in part to the huge jumps in housing costs, making even people with jobs struggle to make mortgage or rent payments.

In Loudoun, the number of families on food stamps has almost doubled since the middle of the recession in 2001, from about 700 to 1,350 in July. The county's median housing price leaped to $454,517 in August from $367,507 last year.

"There are cutbacks in the number of hours people are working in retail and service businesses like landscaping," said Ronald Eamich, assistant director of the county's social services department. "And when you get to a certain point, you start losing your benefits, too, like health insurance, and after a while you come in to see us."

The cuts in hours are probably because of intensified competition, Eamich said. In the past eight months in Leesburg alone, he said, Giant Food opened a second supermarket, and some of the checkouts at the first store were then automated, and a SuperTarget store and a Costco opened. Giant said that is nothing new and that it is always rejiggering the schedules of its workers, three-quarters of whom are part time. According to the company, the automated checkouts increase efficiency.

In Manassas, the number of families receiving food stamps rose by more than 100 to almost 1,400 in August. For all of Prince William County, the average number of food stamp cases a month rose by 500 to more than 4,000 for first half of the year.

"We hear the economy is turning around, and I was expecting our claims to go down," said James E. Oliver, director of the Manassas department of social services. "But we started seeing an increase in all our caseloads two years ago."

To be sure, the federal government has been encouraging more eligible people to apply for food stamps, and in fact cases are up across Virginia. But local social service officials say that is simply one more of several forces behind the jump in cases.

There certainly are jobs but not necessarily high-paying ones. At Okra's Louisiana Bistro, a Cajun restaurant in Old Town Manassas, there was a sign in the window for two waiters for more than three weeks. Okra's pays waiters a little more than $2 an hour to $6, plus tips.

"Waiters are usually a dime a dozen," said owner Charles Gilliam. "Most people have had a job in a restaurant at some time in their life, and they're generally easy to hire."

Gilliam has had better luck trying to hire a chef. His recent Internet ad for the job, which pays as much as $50,000 annually, drew a dozen applicants.

The rise in food stamp applications surprised Stephen S. Fuller, director of the Center for Regional Analysis at George Mason University.

"Part of this is probably because many of the jobs we're adding aren't helping," Fuller said. The hotel industry is booming, but it tends to hire part-time workers, as does retail, he said.

"National retail chains tend to use workers they don't have to pay over 30 hours a week, so they get no benefits," he said. "The average annual wage in retailing has actually gone down."

That is true locally. Paychecks haven't caught up with the cost of housing for many of Prince William's 173,000 workers. About half leave the county every day for what are often better paying jobs in Fairfax County and the District. Those are the people who probably have fewer problems paying their mortgages.

"The high-paying jobs are in those high-rises in Fairfax," said John Hampton, owner of Express Personnel Services Inc. in Manassas. "The reason people are going there is because they can make $50,000 instead of $35,000 here."

That is not likely to change soon. The largest employer in Prince William, Virginia's second-most populous county after Fairfax, is the government. In Fairfax, it's professional and technical services, including the county's wealth of tech employers. In Prince William, retailing is almost a fifth of the workforce; in Fairfax, it is less than 6 percent.

Prince William and neighboring counties are adding residents faster than almost anywhere in the country, which means retail will keep expanding to serve this exploding population. But the jobs don't pay much. At the low end, they pay $7.50 an hour, although some new retailers have started paying as much as $10 an hour, said Ron Stevens, workforce services supervisor for the state unemployment office in Woodbridge.

"With the unemployment rate low, we still get a lot of people looking for jobs," Stevens said. "But they're people with jobs who are looking for a better job or one closer to home."

One of the retailing workers receiving food stamps in Manassas is Heather Stevens, a 24-year-old single mother of two. Stevens said she was laid off two days before Christmas from a clerical job paying more than $17 an hour. She now works at a donut shop for $6.50.

Stevens said she is stretched and has been looking for months for something that pays better because she doesn't want to have to leave the county in search of cheaper housing.

"I send out five to 10 resumes a week," she said. "I get responses sometimes. But I haven't got an interview yet."