No dummy, Terry Kinney.

Kinney, chief of the Agricultural Research Service, knows a signal when he hears it. So when the likes of budget director David A. Stockman and Sen. Charles H. Percy (R-Ill.) began rapping on the wall he got the message loud and clear.

Their message was that some of the 7,000 acres at the Agriculture Department's research center in Beltsville was an example of federally owned land that ought to be declared excess and sold to help trim the national debt.

The Beltsville complex is world-renowned for the work done there by USDA scientists. And sitting athwart busy U.S. Route 1 in a congested suburban area, the complex has been coveted for years by developers who have called it "extremely desirous" and think it would look better in split-levels than fruit trees and corn.

USDA has resisted the pressures, however, on the ground of ground--that is, that the center needed, or will in the future need, every available inch of terrain for the research it carries out. But when the Stockman-Percy message came along, Kinney didn't need to think twice.

"They mentioned Beltsville as surplus," he said last week. "It would have been almost stupid for me to say we don't have any surplus there . . . . A very clear signal had come from the White House."

As a result, Kinney identified two parcels of about 250 acres as expendable.

Those tracts appeared on a recent list of more than 60,000 acres of choice federal properties the Reagan administration wants to sell.

Officials at Beltsville, including its director, Paul Putnam, had recommended that the center hold on to the land, even though it wasn't being "optimally utilized." One official said, "We feel very strongly about it. But it is hard to explain to laymen the value of the land for our research."

Kinney said he agreed that retention of the property could be defended. But he also indicated that he understood the political pressure from an administration committed to harvesting another kind of green stuff.

"Sometimes we have to look at things in the eyes of the people we work for," Kinney said.

The Beltsville listing includes about 240 wooded acres on the west side of the center, not far from the Baltimore-Washington Parkway, which serves as a buffer between nearby residences and entomological study plots. A 13-acre tract, along U.S. 1, has been used for turf research and is identified in the center's master plan as a future building site.

The USDA decision is subject to review and possible reversal by the president's Property Review Board, but that doesn't seem to be in the cards for acreage as potentially lucrative as Beltsville's. (Another five-acre piece of the center's land along U.S. 1 was sold in October for $354,200.)