Montgomery County's proposed new master plan to preserve farmland and open space in the still rural upper third of the county received strong support from citizens at this week's public hearing before the county planning board.

The main criticism of many of the two dozen speakers was that one area -- around Sandy Spring and Ashton -- had not been included in either the designated open space or agricultural reserve areas called for in the plan. It is earmarked instead as a "growth center," along with most of the already developed lower parts of the county.

One resident, Daryl Stewart, an adviser at the University of Maryland and "part-time farmer" on six acres at Sandy Spring, accused county planners of "gerrymandering Sandy Spring out of the agriculture and open space zone . . . and perhaps having a hidden agenda to develop our area."

A neighbor, Gwendolyn Edsall, who said she was speaking as an individual although she is president of the Ashton-Sandy Spring Civic Association, said "Sandy Spring and Ashton will become eyesores like Olney" if not given some protection in the master plan.

"I look out my windows and see nothing but farmland," said another neighbor, Dr. Burton Johnson, who has a 20-acre farm. "Our area looks like Potomac did 20 years ago and we want to keep it that way."

Th plan, which must be approved by both the planning board and the County Council, would designate 114,000 acres as an agricultural reserve and another 20,000 as rural open space.

It recommends several ways to preserve farms and large rural landholdings, including transfer of development rights from designed farm areas to more urban "receiving" areas -- which have not yet been designated -- and the creation of rural cluster zones in areas where subdivisions already have been built.

The cluster zoning, which several speakers urged county officials to make mandatory instead of optional as is now proposed, would maintain the rural open space zoning of one house per five acres, but would cluster the dwellings. If a 200-acre tract were to be developed instead of 40 five-acre lots, the zone would allow 40 houses on 40 percent of the tract (or 80 acres). The remaining 120 acres would be preserved as open space or for farming.

Two developers also backed the proposed master plan. Steve Eckert of Suburban Maryland Home Builders, said "we are very pleased with the plan. But there are three cornerstones in the transfer of development rights (TDRs): a resolving fund, designated receiving areas and designated sending areas. But unfortunately you deal only with the last one."

Planners have conceded that shifting development from some rural areas to still unselected "receiving areass" where greater density will be allowed may be controversial.

Under the TDR program, only one dwelling per 25 acres would be permitted in the proposed agricultural reserve area -- exactly what is permitted under the emergency one-year zoning restrictions voted by the County Council last fall to halt speculation in rural areas while the present master plan was being developed.

Because previous zoning allowed one unit per five acres, however, landowners would be given transferable development rights -- one for each five acres of farmland -- that they could sell to developers planning subdivisions in other parts of the county.

A second public hearing on the proposed master plan is to be held by the County Council on July 9.

A summary, maps and copies of the plan are available at the planning board's Silver Spring office, the county office building in Rockville and at regional libraries.