By HAROLD BROWN

How quickly we forget. Today the push to preserve a single tree in a metropolitan area can become an environmental mission that unites neighborhoods and irritates property owners, produces overbearing ordinances and sometimes results in tragedy when ailing trees damage homes and injure people.

At the same time, the phrase “addiction to fossil fuel” has become a modern-day put-down that it ought not to be. Many today see this so-called addiction as a root problem, yet the benefits are beyond estimate, and long forgotten.

One benefit of our use of fossil energy is the trees we don’t burn. As surely as complaint follows progress, the use of fossil energy saved America’s forests. Until the late 1800s, the yearly consumption of wood for fuel in the United States was more than 300 cubic feet per person.

Today, the nation has about 840 billion cubic feet of wood in its forests and about 276 million people. If we burned that much wood per person today, it would be used up in 10 years.

At the same time that we used the forests for fuel a century ago, an area the size of Georgia, South Carolina and Alabama that could have remained forested was required to feed horses and mules, the main means of transport and agricultural power.

Today we use far more energy per person than then, and not just to fuel our factories and heat our homes. Forests no longer fuel our energy needs: Wood, waste and ethanol accounted for only about 3 percent of U.S. energy use in the 1990s. We get more than twice as much from nuclear reactors, and technology has rendered U.S. energy production cleaner than ever.

Back then, however, fuel was not the only claim on our forests. Much of the woodlands was slashed and burned to make way for cultivated fields and pastures.

Timothy Dwight, a New England minister, wrote in the early 1800s that there were no more than 20 miles of forest on the 240-mile journey from New York to Boston. In the last decade of that century America’s farmers were clearing land at the rate of 3 million acres a year - three times the size of New Hampshire - though most of the clearing had taken place already.

In addition, wood had hundreds of uses in the 1800s that diminished during the next century. Most houses and barns were constructed of wood; replacing railroad ties on a sustained basis required between 15 million and 20 million acres of forest. A smelter producing 1,000 tons of iron a year required 20,000 to 30,000 acres of trees to produce the charcoal. Before barbed wire, America had more than 3 million miles of wooden fences, enough to encircle the earth 120 times.

In spite of claims, even today, that forests are being cleared at “an alarming rate,” the opposite has been true over the last half century. The nation as a whole has about the same acreage of forest as in the 1920s, but Eastern states have reforested dramatically. New York has 6 million more acres than then, Pennsylvania 4.4 million more acres, and Georgia has at least 4 million more. Vermont, 35 percent forested in the 1850s, is 80 percent forested today.

Atlantic Monthly environmental writer Bill McKibben declared in 1995 of the forest recovery, “This unintentional and mostly unnoticed renewal of the rural and mountainous East - not the spotted owl, not the salvation of Alaska’s pristine ranges - represents the great environmental story of the United States.”

None of us are old enough to remember the worst days of forest devastation, but the evidence of recovery is plentiful. The net growth of wood in U.S. forests in 2002 was 3.5 times higher than in 1920. In the last half century, America’s timber growth has outpaced timber harvest, so that the volume has increased by 39 percent. The South did far better with wood volume increasing by 80 percent.

Two of the most decisive developments in America’s forest were the widespread replanting after harvest and prevention of forest fires. Since the 1930s acreage burned each year has been reduced by 90 percent. From 1950 to 2000, the acreage of trees planted yearly in the U.S. has increased from about 0.5 million to 3 million acres. In Georgia alone, planting of trees has increased from zero before the 1930s to a yearly average of 400,000 acres over the last 10 years.

The improvement of our forests is one of the main reasons that wildlife is more plentiful now.

Trees are valued for cleaning air and water, for wildlife habitat and for beautifying the landscape, rural and urban. On all those counts, Georgia and a nation efficiently using fossil fuel are today far removed from that hazy past when we were “addicted to wood.”

University of Georgia Professor Emeritus R. Harold Brown is an adjunct scholar with the Georgia Public Policy Foundation and author of “The Greening of Georgia: The Improvement of the Environment in the Twentieth Century.” The Georgia Public Policy Foundation is an independent think tank that proposes practical, market-oriented approaches to public policy to improve the lives of Georgians.