The Mercury News

February 14, 2005

Want to save giant trees? A chain saw can do wonders

By Thomas Bonnicksen

John Muir called the giant sequoia ``the noblest of a noble race.'' These massive trees, the largest in the world, grow only in the Sierra Nevada. Huge sugar pine and other large trees surround them. ``They are giants among giants,'' wrote University of California professor Joseph Le Conte when he saw the giant sequoia forest for the first time in 1870.

Today, seven times more trees than is natural crowd this irreplaceable forest, and each year it becomes denser. The forest is unhealthy, and the fire hazard is extreme. Yet we have done little to solve the problem.

Now some are suing to block a plan by the Forest Service to deal with the wildfire situation in the Giant Sequoia National Monument. This modest plan calls for removing too few trees to offset even the number of new trees that grow each year. To be effective, the plan should remove more trees to halt excess growth and substantially reduce the number of existing trees.

It seems some people have forgotten the McNally fire of 2002, which burned 151,000 acres and came within less than a mile of the sequoia groves. Jim Paxon, speaking for firefighters, said, ``If fire does get in the Trail of 100 Giants, we won't be putting firefighters in there to try to stop it.''

30 years of research

I know this forest better than most people do. I began in the late 1960s as a ranger in Kings Canyon National Park working on the first prescribed fires and interpreting them to the public. I also conducted research with my colleague Edward C. Stone, a University of California-Berkeley professor, on this forest over the next three decades. Our work forms the basis for the Forest Service plan to restore the monument.

In the 1960s, the Park Service cut intermediate-sized trees before using prescribed fire. It knew that prescribed fire is a crude tool that can cause more collateral damage to a forest than good. The most recent example is the damage it caused to the George Washington Tree. However, a chain saw in the hands of an expert is surgically precise. As A. Starker Leopold, professor and former chief scientist of the National Park Service, said, ``A chain saw would do wonders.''

Unfortunately, some environmentalists stopped the Park Service from cutting trees, and decades of destruction by prescribed fire followed. They would rather see forests burn than cut individual trees to save whole forests.

There are twice as many intermediate-sized trees (up to 30 inches in diameter) today as there were in the historic forest because of 125 years of excluding fire. Prescribed fire cannot reduce the number of trees this size without severely damaging the forest.

In addition, few people realize that unnaturally thick litter that now covers the ground generates so much heat when it burns that even a small fire can kill large trees by cooking their roots. The loss of thousands of huge trees from prescribed fire has become rampant in national parks.

Stone and I warned the Park Service about this terrible loss in 1976. The Park Service conducted a study that shows we were correct. Nevertheless, the destruction continues because they ignored their own study and us.

Now the Park Service has added the 3,000-year-old Washington Tree to the list of casualties from its prescribed fires. This is the second-largest tree in the world, named after the father of our country. Even so, the Park Service refused to protect it from a fire it deliberately let burn.

Watched it burn

The fire took six weeks to reach the Washington Tree. The Park Service had plenty of time to act. Instead, it chose to stand back and watch the fire destroy its top and largest branch. This weakened the tree so much that a recent storm broke it in half. It will probably die.

How could the Park Service let its own prescribed fire destroy a national treasure and many other giant trees? It could have saved all of them. It takes only a few minutes and a garden rake to clear thick litter from around a tree to keep fire away.

I cannot speculate on why some people would rather see huge trees and whole forests killed by fire rather than use 21st-century knowledge and tools to prevent the destruction. I just know that the anti-management philosophy is no justification for sacrificing national treasures.

Let's use common sense and the best available science to make decisions about our forests. This is not about politics. This is about protecting our national heritage.

THOMAS M. BONNICKSEN is professor emeritus of forest science at Texas A&M University, visiting professor at the University of California-Davis and visiting scholar at the Forest Foundation, which is supported by the California Forest Products Commission. He wrote this article for Knight Ridder.

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