Babbitt shuts off prescribed fires in West for 30 days

Blazes at North Rim, Los Alamos spur Interior boss to act

Interior Secretary Bruce Babbitt yesterday suspended the use of prescribed fire on federal lands in the parched West for 30 days.

Two of the four large wildfires burning in the Southwest started as intentionally ignited National Park Service burns designed to clear unwanted brush.

Babbitt's action was prompted by the fires in Los Alamos, N.M., and on the Grand Canyon's North Rim. The move will have little effect in Southern Arizona, where federal firefighters have already completed their prescribed burns for the season.

"We've pretty much got all our stuff done," said Rich Kvale of the Coronado National Forest.

The Coronado burned 5,800 acres this season, including fires southwest of Sierra Vista near Parker Canyon Lake, southwest of Safford on Mount Graham, in the Chiricahua Mountains of eastern Cochise County and in the Santa Catalina Mountains north of Tucson.

The Forest Service had planned a 1,700-acre fire near Safford for the end of this month, but it was canceled earlier this week because of extreme fire conditions.

The U.S. Fish and Wildlife Service burned several thousand acres of grassland this spring at the Buenos Aires National Wildlife Refuge southwest of Tucson.

Saguaro National Park is planning a 3,500-acre fire on the southwest slopes of Mica Mountain in the Rincons east of Tucson, but ignition is scheduled for the fall, said park fire management officer Chuck Scott.

"We'll have our plan built and be ready to go," he said.

During the 30-day suspension and for months to come, the risks and benefits of using prescribed fire as a forest-management tool will be debated.

Tighter controls on the use of prescribed fire may be imposed. But no amount of regulation can eliminate all the risks inherent in mimicking Mother Nature's use of fire, experts said yesterday.

Even so, the ecological benefits of prescribed fire outweigh those risks, fire and forest experts said.

"Prescribed burning is an integral part of restoring forest ecosystems. How and when we burn, not whether or not we burn, is the difficult issue," said Taylor McKinnon of the Flagstaff-based Grand Canyon Trust.

Prescribed-burn specialists walk a tightrope. Their goal is to ignite a fire that burns hot enough to consume unwanted trees, brush and grass without unleashing a runaway firestorm.

The "prescription" for an intentionally set fire refers to the conditions under which the fire can be safely ignited and will accomplish objectives detailed in a burn plan written months beforehand.

Variables in the prescription include temperature, relative humidity, wind speed and direction, and moisture content of the fuels.

Last month near Oracle, the U.S. Forest Service attempted to burn 180 acres as part of its ongoing effort to create a "buffer zone" around the town to shield it from a catastrophic wildfire.

The goal was to kill 40 percent to 60 percent of the oak and manzanita in the burn area, said Ted Moore, a Forest Service fire management officer.

To achieve that, the prescription called for air temperatures between 80 and 95 degrees, relative humidity between 8 percent and 20 percent, and winds between zero and 15 mph.

Firefighters were hoping for flame heights between 3 and 8 feet, and they ignited a small "test burn" to check conditions. Flames jumped to 10 feet, and the fire burned much hotter than expected, so firefighters decided to shut it down.

But an ill-timed wind shift blew embers across the fire line, and flames raced to within one-quarter mile of several homes. The out-of-control fire scorched 80 acres, Moore said. Five months of planning went into that Oracle burn, and the cost will probably exceed $40,000, he said.

More than eight months of planning went into Saguaro National Park's 2,000-acre Chimenea burn in October 1998, Scott said.

In addition to preparing a detailed burn plan, fire managers worked with the Arizona Department of Environmental Quality on smoke-management issues.

They had to assure biologists that the fire would not harm threatened, endangered and sensitive plant and animal species. They demonstrated that archaeological and historic sites would be protected.

In addition, they simulated the fire using a computer program called "Behave."

"These are not spur-of-the-moment. You don't just wake up one day and say, 'Well, let's go burn 2,000 acres,' " Scott said.

Because a lot of time, effort and money goes into preparations for a large prescribed burn, fire managers sometimes feel pressured to "see it through" — even when conditions aren't optimal, Scott said.

"But this is something we've talked and talked a lot about at regional and national meetings," he said. "You don't want to feel under the gun. You have to use your professional judgment and use all the information you have in front of you at the time."

Reporter Jim Erickson can be reached at 573-4197 or by e-mail at erickson@azstarnet.com