Tree farming takes patience, and Jim and Connie Dunbar have spent much of the past decade quietly planting stands of walnut, oak and loblolly pine on their farm here in Charles County.

"Oak is something you plant for your grandchildren," said Connie Dunbar, whose husband was chosen Charles County's tree farmer of the year in 1985.

But their trees are still saplings, and their dreams are fading rapidly. The county wants to build a runway on some of their land as part of a new county airport.

The proposed $10 million airport just north of La Plata, which would serve general aviation aircraft such as single- and twin-engine planes and business jets, has brought unexpected animosity to one of the most rapidly growing parts of Maryland.

The airport was first proposed by the Federal Aviation Administration, which would pay 90 percent of the cost of development. The new facility, in addition to serving as a base for local aircraft and corporate planes, would help relieve National Airport of some of the smaller aircraft that compete for landing space with scheduled carriers, according to the FAA.

County economic officials say that the air park, which would be owned by the county, is essential to attract business to the area. But many residents, wary of patchwork development, are fighting the plan, arguing that the airport would prevent growth rather than spark it.

"We need orderly economic development down here, not foolish dreams," said Russell Levin, a county resident who runs an aviation insurance company and is a member of STAN -- Stop the Airport Now. "Quality education and good roads attract businesses. It takes more than an airport," he said.

The county commissioners approved the controversial plan to build the airport on 350 acres just east of Rte. 301 between St. Charles and La Plata by a 2-to-1 vote last month. County officials, who are working on a comprehensive master planning study to judge the impact of the airport, said construction could begin within a year following state approval, which is expected.

County planners project that the airport could handle 12,000 takeoffs and landings a year in 1988 and as many as 105,000 in the year 2008.

County officials say the airport would create more than 1,000 new jobs by sparking nearby development, and would within a decade bring the county millions of dollars in annual income.

They are planning a new two-lane road to connect Rte. 301, the county's major north-south thoroughfare, to the airport. But critics worry that one new road will not be enough to accommodate the traffic.

"You should see the backups we have now on 301," said Leo F. Smith, who founded STAN with Connie Dunbar. "Tell me how it's going to get better if we have hundreds of people using this airport as a way to get to Washington?"

Supporters say that the airport will help Charles County make the shift from a commuter county -- almost 75 percent of its work force now has jobs in other counties -- to a place where residents can find jobs.

"Big changes are coming for this county and we need to be prepared for them," said Ray Tilghman, director of the county Economic Development Commission and an advocate of the airport. "We are really the last great growth area in the metropolitan region and we need to bring tax dollars here, not just commuters. The airport will be an essential marketing tool."

Growth is a prime concern in Charles County. By the year 2000 its population is expected to increase to 112,000 from the current 84,000, according to the state Economic Development Commission. More than 130 families -- many of them from more congested suburbs of Washington -- are moving into the county each month.

Opponents of the airport had urged the county commissioners to hold a referendum on the issue, but they declined, saying that it was their duty to move fast to provide jobs for people living in the area.

"It would be irresponsible not to take advantage of this opportunity," said Loretta Nimmerichter, a commissioner who, along with Chairman Marland Deen, voted in support of the project.

The third commissioner, Eleanor Carrisco, was the dissenter.

Most of the opposition to the airport comes from people who believe that money needs to first be invested in other areas, particularly education. Charles County ranks in the bottom half of all Maryland counties on standardized test scores, while neighboring Calvert County and other Washington area jursidictions have traditionally been near the top.

"This is not a no-growth argument," said state Sen. James Simpson, who represents the county. "It is about priorities. Nobody has been a bigger booster of economic development here than I have. But we need to lay down the foundation first. First, let's pay our teachers better. Then we can talk about airports."

Some people in Charles County feel as if they have lived through these battles before.

Barbara Beard and her husband are among those who left Prince George's for what they thought would be the more rural surroundings of Charles County. They followed area newspapers through the 1970s to track the growth of the region, bought land near La Plata in 1979 and moved there in 1984.

She was unprepared for the plan to bring an airport to within three miles of her home.

"If we wanted to live near an airport we would have moved to Montgomery County," said Beard, who has become active in STAN. "This is country living at its best. But what bothers me is not the development -- some of that is inevitable -- but the fact that they rammed this through without paying any attention to what people said at hearings. It's like the commissioners didn't even listen to the words that were spoken to them."