Arlington neighbors who are thinking of packaging their properties to sell to developers were put on notice yesterday by the County Board that it will not buckle under to pressure for rezonings and land-use changes that might make certain properties more valuable.

The board members, unanimously adopting a resolution from board member Albert C. Eisenberg discouraging such change, said they have become increasingly distressed by the recent trend of some neighborhood residents seeking high-rise rezonings and extra densities in hopes of getting more money from developers for their land packages.

"The major problem of homeowners going into business for themselves is that they add more pressure for density" than is consistent with the zoning and land-use designations that the county believes is appropriate for some sites, Eisenberg said.

Such actions cause "destabilization of already fragile neighborhoods" and weaken the quality of neighborhoods, Eisenberg's resolution said.

The trend, sometimes called "neighborhood-busting," has emerged in Arlington in recent years as developers have snatched up homeowners' invitations to buy their properties in a block rather than individually as nearby areas have exploded with high-rise redevelopments.

In return, the homeowners sometimes have received three times the assessed value of their properties from developers who might not otherwise have been able to consolidate the prime land so quickly, if at all.

The board members made it clear that they were not talking about consolidations in neighborhoods that the county has designated for intense redevelopment, such as areas immediately surrounding Metro subway stops. "That's an important distinction," said board member Mary Margaret Whipple, emphasizing that not all consolidations would be discouraged.

As an example, the board cited the 22 homeowners in the Courtlands neighborhood near the Court House Metro stop, who earlier this year sold their properties for $10 million to a developer who plans to build a $125 million residential-retail complex on land previously slated for high-density development. The board narrowly approved the complex in January.

In June, another group of 20 Courtlands neighbors announced similar plans to sell their land adjacent to the other approved project; the board has not yet approved the second proposal.

Also in June, a group of 36 homeowners in the Avon Park and Jordan Manor subdivisions just west of the Ballston redevelopment area unveiled plans for a consolidation. But unlike the Courtlands consolidations, their neighborhood is considered a crucial buffer zone between Ballston's redevelopment and single-family neighborhoods. As such, the county -- to the relief of other owners of single-family homes nearby -- has designated the area for low-rise town house redevelopments only.

"I'm particularly concerned about what's happening in Jordan Manor and Avon Park," said board member Michael E. Brunner, who has previously expressed alarm at the trend. He added that citizens should be aware that the county is "not looking for big developments from neighbors coming in and selling their houses."

"It is the job of the board to plan land use," said board member Ellen M. Bozman. "It doesn't matter who owns the land or who consolidated it."

Board Chairman John G. Milliken said, "The important thing is that your property is compatible with what the county and the community feels is right there. If it isn't, it doesn't matter who's behind [a consolidation]."