In an effort to block development and preserve rolling meadows for parkland, Gaithersburg city officials plan to buy a 60-acre farm on the city's southern edge for $3.5 million.

The land would be set aside for recreation, possibly including a park, swimming pool, farm museum, senior center or small zoo, City Manager Sanford Daily said.

The city acted because developers recently have indicated heightened interest in Summit Hill Turf Farm, west of Rte. 355 between Summit Avenue and Deer Park Road, Daily said. The developers "could produce a large number of town house developments and traffic problems," he said.

The price would be the highest the city ever has paid for a single tract, Daily said.

The city has put down a $25,000 deposit with Ruth E. Wilmot and Francis W. Kellerman, owners of the sod farm, to hold the land until Nov. 30 while officials try to arrange financing.

Under the agreement between the city and the owners, the city would buy all but a house on a one-acre parcel, where Kellerman would be allowed to live.

Daily said the city would maintain ponds, historic dwellings and a log smoke-house on the farm.