Less is more. For the second year running, this is the theme of Montgomery County Executive Charles Gilchrist's recommendations for future building and repairing of roads, schools, recreation centers and other high-cost capital projects.

The call for austerity comes after a decade of rapid growth in building and indebtedness in this wealthy Maryland county that Gilchrist now fears is becoming overextended. In a three-volume study released yesterday, he proposed holding capital spending in the coming six years to $1.1 billion, down from the $1.4 billion proposed last year.

The annually updated Capital Improvements Program provides for 740 public facilities that the county expects to construct or renovate by 1987. It goes to the County Council, which will begin public hearings in late January.

Citing "an environment of ever-diminishing resources," Gilchrist called for limits on new building and bond issues and deferral of certain projects already on the books -- mostly roads and park land acquisition in the upper county. Disappropriation of funds already pledged to 22 projects could save $12 million, he said.

Parking Garage 49 in Bethesda should be shelved, county planners say, until legal action actually acquires the land. Unsolved water pressure problems also make the Upper County Pool and Recreation Center in Emory Grove a prime candidate for deferral.

Gilchrist recommended a moratorium on acquisition for the stream valley parks program, saying that the agricultural preservation zones being developed offer "a major new tool" for conservation of rural areas.

The study also called for a "realistic school maintenance and renovation program." Plans to remodel a high school, a junior high school and three elementary schools and to build three gymnasiums yearly "appear overly ambitious."

Despite the call for economy, county officials insist that an unprecedented number of capital improvements are under way. The job is to rein in the expansion and draw down the reservoir of projects already under way.

Population growth in the last decade fell short of expectations, which Gilchrist said makes him doubt the wisdom of rapid capital expansion. School-age population, for instance once projected for 120,000 in 1980, now is expected not to be more than 105,000 by 1985.

Moreover, interest rates for Triple-A bonds floated on Wall Street to finance development have risen rapidly. Last year, the county obtained rates of about 6 1/2 percent yearly. Recently, interest rates of 10 percent have been asked in New York.

Gilchrist proposed holding new bond issues to $420 million over the next six years, down from $588 million that his staff proposed. Despite such efforts, officials expect the county's total obligation of bond principal and interest to almost double to $1 billion by 1988.

"Urban amenities" were the only new projects Gilchrist suggested for immediate implementation, which included improvements to the Rosemary Hills Recreation Center and development of three parks in Silver Spring, Takoma Park and Gaithersburg.

Gilchrist's efforts to cut spending could be compromised in the County Council, as members raise objections to his choices for cuts. Last year the council tacked close to $200 million on to his original proposal of $1.4 billion.

According to Councilman Neal Potter, "there is considerable feeling that we have to hold things down." However, Potter questioned Gilchrist's apprehensions about borrowing. Interest rates may be high, he argued, but they are still far below inflation. For capital intensive projects, borrowing and building now often means "the ultimate burden on the taxpayer would be lower," he said.