FOCUS ON FIRE
IN THE FOREST
FUNCTION OF FIRE
A GRASP ON SMOKE
BEYOND THE BLAZES
in the Forest
That forests and fires go together is a given.
But in recent years, they haven’t gone together well. Intense infernos have blackened thousands of acres of pine forests and killed the big trees that once benefited from fire. Fire suppression, past logging and successional changes have resulted in high fire hazard over large areas of the United States.
How best to pull forests and fires back into harmony is the goal of an unprecedented national research effort involving UM.
In a network of 13 research sites stretching from Washington to Florida, scientists are looking at how best to return fire to a positive in the ecosystem. At UM’s Lubrecht Experimental Forest, a 28,000-acre outdoor classroom and laboratory east of Missoula, a study funded by the National Joint Fire Sciences program is tackling this question.
UM Research Professor Carl Fiedler leads a team of four College of Forestry and Conservation faculty who direct the Montana portion of the study.
“Four hypotheses drive the treatments being tested,” Fiedler says.
On three separate 100-acre parcels within Lubrecht Forest, UM researchers have carved out four 25-acre treatment units.
In one, they thin trees to restore forest structure.
On another, they use prescribed burning to restore the process of fire.
On a third, they use a combination of thinning and burning to restore structure and process.
And on the fourth, they do nothing.
“It’s called passive management,” Fiedler says of the fourth hypothesis. “The idea there is that nature knows best.”
is, for millennia, nature did. But man’s
involvement in the last century, through fire suppression and sometimes
careless logging, has created a different kind of forest — and
a different type of wildfire.
At UM, it means four graduate students have been fully funded for three years to study invasive plants, soil nitrogen cycling, bark beetles and wildlife responses. Another 15 to 18 undergraduates have worked as research assistants in a study.
“We want to do things that have the most positive, and least negative, effects on a forest,” Fiedler says. “We’re not just looking at reducing fire hazard. We’re looking holistically at the forest, at the density, structure and species composition of trees, as well as other plant, animal and soil components that make up a forest.”
treatment unit is subdivided into many smaller plots for detailed
study. Treatment effects on vegetation, including tree growth and
mortality, are measured. So is “understory” vegetation,
Woody fuels — their size, volume and arrangement — are intensively sampled. UM researchers also monitor small mammal populations and the feeding habits of bark-gleaning birds.
The physical, chemical and microbial properties of soil are studied, as are insects (primarily bark beetles) and the volume and value of timber products removed.
Companion studies are being conducted in Alabama, North and South Carolina, Ohio, Florida, Washington, Oregon, Arizona, New Mexico and California. Researchers from the National Park Service, the U.S. Forest Service, UM and the universities of Washington, California at Berkeley, Ohio State and Clemson are involved.
“To look in detail at only one location would give us good, but restricted, data,” Fiedler says. “In different environments you may get similar or contrasting results. Either way it’s valuable information that can be used at the local, regional or national level.”
He calls it “value-added results.”
“We have core variables we’re all measuring in the same way,” Fiedler says. “It’s very different than if we were all doing our own thing.”
Meta-analysis — the combining and analysis of data from a number of similar studies — has its origins in the medical field and is just now coming into its own, Fiedler says.
example, if 10 or 11 of 13 sites
have a common response in a variable, that’s pretty powerful,” Fiedler
It’s not easy to obtain. Half of the study involves fire — three units treated with fire alone and three with a combination of thinning and prescribed fire.
“You make a mistake with a chain saw, and you kill one tree,” Fiedler
says. “Make a mistake
with fire, and you’ve
Alamos fire of 2000 in New Mexico started
as a prescribed burn that
ended up torching nearly
Low-intensity fire traditionally thinned out smaller trees and ground fuel, but fire suppression has changed the look and flammability of forests. Where once trees were scattered across open areas, today forests are as crowded as Grand Central Station. Younger sun-starved pines may only reach a height of 3 feet after 30 to 40 years, and intense wildfires now burn through dense forests killing everything in their path.
Researchers use historical photographs and journal accounts to determine what forests looked like a century ago, before fire suppression and logging changed the face of the forest ecosystem.
Early results of the study, Fiedler says, indicate that a combination of thinning and burning is most effective in reducing the fuels that spark intense wildfires. This treatment also is best for increasing native plant diversity, nitrogen availability for plant growth and foraging habitat for woodpeckers and nuthatches.
But it also creates the most hospitable conditions for invasion by exotic plants and noxious weeds, increases deer mice — considered a “pest” — and discriminates against red-backed voles, a species beneficial to forest growth and regeneration.
It may be, Fiedler says, that a combination of thinning and burning serves up not only the most positive effects, but also the most negative.
There is still much to be learned, and Fiedler says the longer the study runs, the more relevant the results will be. Though none of the treatments appears to be a “silver bullet,” wildfire in today’s dense forests would be a magnitude greater intensity than any treatment being tested at Lubrecht, with correspondingly greater impacts.
“The forest has almost morphed in front of our eyes,” Fiedler says. “The forest of today is not the forest our parents or grandparents knew.”
Getting that forest back — a vigorous, sustainable, resilient forest — is a tall order. And one, at The University of Montana, people such as Carl Fiedler are tackling.
For more information, e-mail Fiedler at firstname.lastname@example.org.