The police drive Volvo squad cars and the city offers gardeners leaf mulch for free.

The high school offers a hundred courses to its 322 students, ranging from word processing to parenting.

The city has its own library, soon to be open seven days a week, its own water system, even its own nonpolitical political party, the Citizens for a Better City, to which all seven City Council members belong.

Welcome to historic, tree-lined Falls Church, "a family-oriented urban village," according to its literature, and the city the Census Bureau has just ranked as having the second highest per capita income in the country.

Only Bristol Bay, Alaska, which had a per capita income of $14,948, was richer than Falls Church which has an income level of $12,885.

All of which came as something of a surprise to officials and residents of the two-square mile incorporated city of 9,500 that is sandwiched between Arlington and Fairfax County. Demurred Mayor Carol W. DeLong yesterday: "I don't regard Falls Church as a rich community. Comfortable, yes. Rich, no."

DeLong attributed the city's high incomes to the high levels of education of city residents, to the existence of many two-income households, and to the relatively small size of families that are found in the city.

"We may have high incomes," she said, "but we also have high outgos. It's expensive to live in all of Northern Virginia, so you figure if people are going to live here, they have to be able to afford it. People here do well, but this is by no means a wealthy community."

Falls Church is not, however, a city for the poor. Of the city's 4,475 housing units, only 114 are publically subsidized, and 80 of them are reserved for low- and moderate-income elderly and handicapped people. And while the assessed values of houses in the city do not exceed $350,000, the average assessed value of housing there is $106,000.

Only 15 percent of the city's taxable land is commercially occupied and there is no industry, so the city is not attractive to blue-collar workers. Unemployment is slightly below 4 percent, compared to 7.3 percent statewide, according to latest figures.

All-in-all, that has given Falls Church a rather homey, small town image. It is an impression that the city fathers like to encourage, noting in brochures that the community was settled in 1699, that it has 44 memorial historic trees, and a church, after which the town was named, that is 250 years old and once counted George Washington and George Mason among its worshippers. The city's major thoroughfares, Leesburg Pike and Lee Highway, were originally Indian trails.

The streets are cleaned mechanically once a week, and unlike Rosslyn, its high-rise neighbor to the east, the city has no buildings more than five stories high. City ordinances require shrubs and greenery between housing units and businesses and specify that no sign may occupy more than 50 square feet. There is even an $8,200 line in the city budget for Operation Match, a "roommate service with a heart," for elderly and financially strapped citizens.

"It's a very interesting city in that it attempts and accomplishes the business of making a homelike place to live," said Donald B. Wilson, executive director of the Falls Church Chamber of Commerce.

"It's low key . . . You don't get the impression it's so rich. It's not a flashy town. It's refreshing."