On a cold day warmed only by a pale sun, a group of Fairfax County officials, conservationists and representatives of local businesses Tuesday dedicated a 25-foot white oak tree to the memory of Puller A. Hughes Jr., for 22 years a driving force behind conservation efforts in Northern Virginia.

Hughes's tree was planted in the Meadowlark Gardens park in Vienna, in a small copse next to a lake filled with Canada geese resting on their way south for the winter. As the onlookers watched the dedication, clusters of the oak's few remaining leaves were blown off the tree and scattered over the lake by the brisk wind.

After the dedication, the group made its way up to a small 17th-century farmhouse where, over hot cider, Fairfax County Board of Supervisors Chairman Audrey Moore presented Hughes's widow with a copy of a resolution passed by the board expressing appreciation for his lifelong devotion to the environment.

Hughes's finest accomplishment, Moore said later, was protecting the Pohick Creek region. As chief engineer of the Fairfax Field Office of the U.S. Department of Agriculture during the mid-1970s, he built dams and lakes to hold back water and prevent erosion.

"Getting that land, getting the money and keeping it going was a tremendous challenge," said Moore. "What it means in that area of the county is that the streams look exactly like they originally did, because there are lakes there to hold back flooding waters."

Jean R. Packard, vice chairman of the Northern Virginia Regional Park Authority, a director of Northern Virginia Soil and Water Conservation District and longtime friend and colleague of Hughes's, said, "I can't think of a more appropriate way to pay tribute to Puller and what he did for the natural resources of Fairfax County than with this tree."

Chris Bogart, who organized the initiative to honor Hughes with the tree, said he chose the white oak, a native of Virginia, "as a symbol of what Puller represented," because, like Hughes, "it dominated the landscape."

Julie Maloney, of the regional park authority, who helped raise money for the "perpetual upkeep" of the oak, said that choosing the tree as a memorial was an appropriate way to remember Hughes "with something that is living and growing."

After his retirement in 1979, Hughes served for 10 years as executive director of the Northern Virginia Soil and Water Conservation District. He died in March.