WASHINGTON—Despite a booming population and urban sprawl, the United States has gained 10 million acres of forests since 1990. That's enough trees to cover all the land in New Jersey twice.
The increase, however, is spotty and probably temporary. Growth is concentrated in the Northeast and Rocky Mountain states, while wooded acres dwindled in the South, Midwest and Pacific Coast.
"We're continually growing more than we're cutting," said Brad Smith, an authority on the nation's estimated 3 billion trees at Forest Service headquarters in Arlington, Va. "People think urban sprawl is eating all the forest—we can't say that."
Over the past 50 years, according to the Forest Service, 24 states added woodland —seven of them more than a million acres each. New York, Ohio and Pennsylvania were the biggest gainers. Texas, Florida and California lost the most.
To be sure, the newly planted timber isn't the same as pristine old-growth forests, but the United States is a rare bright spot in a world that's rapidly losing its forests. Worldwide, 235 million acres of trees vanished in the last decade, as much as all the land in California, Pennsylvania, Ohio, Minnesota and North Carolina combined.
Africa and South America lost the most, while Europe and China gained. China is adding an average of 4.5 million acres of trees per year under a massive reforestation program.
When European settlers began to colonize America in the early 1600s, forests covered more than a billion acres—about half the territory that eventually would become the United States—according to Douglas MacCleery, a Forest Service historian.
Colonists cut down trees for fuel and farmland, and a long, slow decline of forests began. It hit bottom in 1920, when only 735 million acres of woodlands were left. By that time, 370 million acres of trees—one-sixth of the nation's land—had been taken over by farms, cities, homes and industry.
"In the 1920s, the inexorable, three-century-long conversion of United States forests to farmland largely halted," Ralph Alig, a Forest Service economist in Corvallis, Ore., wrote in a report on forest trends from 1630 through 2002.
The main reason, he said, was the switch from a country primarily based on agriculture to a modern industrial and commercial economy.
Large, efficient farms in the West replaced millions of small holdings in the East. Farm machinery and tractors took over from horses and mules, which needed a quarter of the cropland for their own food. Abandoned pastures reverted naturally to forest. Heat and power came from coal, oil and gas instead of wood.
In addition, wildfires, which used to consume as many as 50 million acres a year, have declined to burn less than 5 million acres a year, thanks to new technologies and better fire control.
Government policies also have helped. A belt of trees was planted from the Canadian to Mexican borders under the Soil Bank program of the 1950s to prevent a return of the "Dust Bowl" of the 1930s. Tax incentives under the Conservation Reserve Program of the 1980s and `90s led to widespread tree-planting.
More trees are growing now than are being cut down. "Over the past 50 years, net growth has consistently exceeded removals in the United States," said Smith, the tree expert.
As a result, the land area covered by forests has risen slightly, from 735 million to 749 million acres. Trees now occupy one-third of the nation's territory.
There are significant differences among the states.
Only 10 percent of the land in Ohio was forested in 1910, according to the Ohio Department of Natural Resources. Today trees cover more than 30 percent of the state, although its population has more than doubled.
"Ohio was one of the first states in the country to develop a forestry program to provide incentives for landowners to protect woodlands and prevent fires," said John Dorka, the chief forester at the Ohio Department of Natural Resources.
New York has almost 6 million more acres of forest than it did in 1920. Pennsylvania gained 4.4 million acres. Almost 90 percent of the state of Maine is tree-covered, up from 62 percent a century ago.
"Eastern forests have staged a major comeback," said MacCleery, the historian.
Texas, on the other hand, has lost 8 million acres since 1920, and Florida almost 4 million.
Unfortunately, the gains are unlikely to last. The Forest Service projects that all areas of the country, even the Northeast, will lose woodlands by 2050. By that time, economist Alig said, the nation will have 150 million more people than it does now, and about 23 million fewer acres of forest.
For more information on U.S. forests on the Web, go to www.fs.fed.us/pl/rpa/list.htm
Forest Service data for all states, covering somewhat different time spans, is available at http://ncrs2.fs.fed.us/4801/fiadb/rpa_tabler/Draft_RPA_2002_Forest_Resource_Tables.pdf. Scroll to Table 3.
(c) 2005, Knight Ridder/Tribune Information Services.
PHOTOS (from KRT Photo Service, 202-383-6099): ENV-FORESTS
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