Crews  deliberately  torch  wetlands
September 23, 1998
The Register-Guard - Used with permission

The fire started Tuesday afternoon with a small plume of smoke near a grove of ash trees at the south end of a meadow. Then it inched across 19 acres of wetlands to the edge of West 18th Avenue - helped along by more than two dozen federal firefighters.

Burning wetlands? Huh?

It sounds strange, but it's not. The Nature Conservancy, which owns the plot and another eight-acre patch that was also burned Tuesday, uses fire as a restoration tool.

Ed Alverson, who manages the Nature Conservancy's 392-acre Willow Creek wetland preserve, said Native Americans periodically burned "wet prairie" wetlands - such as the ones burned Tuesday - over thousands of years.

The failure to continue the practice over the last 150 years, since white settlers took over the Willamette Valley, is one reason so little native prairie remains: less than a half-percent of the valley's original 1 million acres, Alverson said. Another 600,000 acres of woodland and "savanna" types of wetlands are also gone.

Non-native plant species have invaded the conservancy property and most of the 1,300 acres of publicly owned wetlands in west Eugene, crowding out native species that once thrived. Some, like Bradshaw's lomatium and the Willamette daisy, are so rare that they've been protected under the federal Endangered Species Act.

So for the past decade, the U.S. Bureau of Land Management and Nature Conservancy have staged "prescribed" burns in the fall or spring in an effort to restore these wetlands.

Land managers have found that the slow-burning fires kill off many unwanted species, such as ash trees, and actually help many native plants regenerate and thrive.

"The Nature Conservancy nationwide is trying to build a fire program," said Oren Pollak, Oregon director of stewardship for the environmental group. "The Nature Conservancy is beginning to recognize the need to do prescribed burning. We bought these preserves to maintain them; fire is one way to do that." In Oregon, the group manages 73,000 acres in 50 preserves.

Tuesday's burn was one of the largest attempted in west Eugene and the first on Nature Conservancy property since 1996.

With five BLM and U.S. Forest Service firetrucks wetting down a perimeter, firefighters used drip torches to set the meadow on fire once wind conditions were right. The humidity also had to be in a certain range: dry but not too dry.

It took about two hours to burn the first 19 acres. Then the crews moved to the smaller patch nearby. The wind direction held, allowing the smoke to rise high and drift toward the south, away from Eugene and the Hyundai plant.

Alverson said prescribed burning is always a tradeoff. While it helps stimulate some native plants, it can be bad for other plants or wildlife.

For example, a study of a burn on some Nature Conservancy wetlands near Salem found that it killed nearly all the larvae for the rare Fender's blue butterfly. The butterfly feed primarily on Kincaid's lupine, which appears to be helped by the burning, Alverson said.

"It's a real paradox," he said.