Native Fire
DB: This is Earth and Sky. For thousands of years, large tracts of North America saw episodic wildland fire – fire that was natural and even necessary for local ecosystems.
JB: Dr. Wendel Hann of the U.S. Forest Service calls the natural cycle of wildland fire “native” fire. He says that, like native species of plants and animals, native fire plays a critical role in many ecosystems.
DB: That’s because many forest creatures are “fire-adapted” – like the three-toed and black-backed woodpeckers. Fires leave behind excellent feeding conditions for certain insects, and the woodpeckers need these insects in their diets. When fires don’t burn, the insects decline – and so do the woodpeckers.
JB: Researchers like Wendel Hann study the history of fire – for example, they might look for fire scars in living trees. If you remove a bore from a tree, you can sometimes see a blackened and damaged area within the trees’ rings. These researchers have found that, in a natural state, fire occurs periodically in forests and rangelands. This native fire clears out the vegetation and fuels, so that when fires do burn, they aren’t so catastrophic. Hann believes the lack of native fire in forests and rangelands has lead to ecosystems that are dangerously out of balance. But he thinks the balance can be restored – as researchers begin to understand the value of frequent, low-impact fires. We’re Block and Byrd for Earth and Sky.
Our thanks to the following individuals and institutions who assisted in
the preparation of this script:
Thanks to:
Dr. Wendel Hann
U.S. Forest Service Fire and Aviation Management
Leadville, CO
Author’s Notes:
Interview with Wendel Hahn:
There are several ways that we establish the history and impact of native fire on a given landscape. When trees burn, telltale scars are left behind that tell us about when the fire occurred and about its intensity. From these scars-which we examine from boring a tree, or looking at a complete horizontal cross-section-we can determine the interval of natural, or
native, fire in certain areas.
In addition, we look at native plant and animal species in an area and whether these species exhibit any adaptations to fire. Bunch grasses and ponderosa pine, for example, are classic “fire-adapted” species. The trees have a thick, fire-resistant bark and cones that require fire to open and release their seeds. The grasses have long roots that are not nearly as susceptible to fire as the grass blades themselves-so the grasses can re-sprout quickly after a fire burns through. Plus, there are other species that require fire for their seeds’ germination. Some seeds can wait for up to two to 300 years in soil waiting for the effects of fire to stimulate their germination. “These species make a living with fire,” says Hann.
Some species of woodpecker-like the 3-toed and the black backed-also make their living from fire-disturbed landscapes. They feed on the insects that arrive to bore into burned wood immediately after fires burn. These woodpeckers are actually in trouble now because there’s so little fire. The birds are having a hard time finding enough insect food. After the woodpeckers bore holes in search of insects, mountain bluebirds come in and use these holes as nesting cavities.
Now there are long intervals between fires because of fire suppressions. And fire suppression has its roots in our ancestors’ ignorance of native fire in the North American landscape. When settlers arrived and saw fire burning on the landscape, they were very fearful since they hadn’t experienced such fire in their European landscape. So fear was the initial impetus to put out fires.
Native fires were typically light burning, and relatively easy to put out. But now, with all the fuel that has built up with fire suppression efforts, the fires that burn are very different-they are catastrophic. Instead of “maintenance” burns, we’re seeing catastrophic fire. “It’s a totally different kind of burn now than before (when native fire was allowed to burn). These catastrophic fires burn the soil surface and allow erosion to occur resulting in the loss of soil material that took 10 thousand years or more to develop. In addition they kill the fire-adapted species that would have survived the native fires. When current catastrophic fires threaten homes there is little we can do to protect the homes, while protection of homes from fires burning at more natural intensities are relatively easy. Most firefighter fatalities and severe accidents are associated with these catastrophic fires when firefighters are trapped and these fires blow-up and rapidly burn through the crown across large areas.
“We can do mechanical or hand pre-pretreatment that will reduce the fire intensity to lighter burning fires. These treatments help remove fuel and prepare an area for a low-impact prescribed or wildland fire,” says Hann. “But many of our fire-adapted landscapes are now in a very serious condition because of 100 years of fire suppression and 100 years of European-style forest and range management that has changed the native landscape to an unsafe and exotic landscape . Because of this, it’s easy for me to understand the increase in listing of many species (as threatened or endangered) that associate with fire-adapted habitats, as well as the increased risk from fire to houses and firefighters. The system is really out of balance-out of whack.”
“What we need to do (to get the system back in balance) is restore landscapes through use of mechanical and hand treatments to reduce fuel, combined with prescribed burning. Once we restore landscapes, then we can step back and let many wildland fires burn with little risk to ecosystems and people. However, it took us 100 years or more to arrive in our current high risk situation, so it may take us another 100 years to restore the balance,” adds Hann.
Now the president, congress and the forest service are working on a cohesive management strategy to be incorporated into the National Fire Plan. The plan calls for aggressive hand and mechanical treatments, coupled with prescribed fires and use of beneficial wildland fires (letting those lightning ignited fires burn that can achieve objectives). Because of the last season of catastrophic fires all over the West, and the fact that the last 6 out of 10 years were quite bad fire-season years, there is a lot of public and congressional support to move the plan forward. The plan calls for a large increase in forest and rangeland landscape scale restoration starting in 2001 and continuing for 10 to 20 years until much of the western landscapes are restored and can be maintained.
Says Hann, “The data speak for themselves. If you take only a simplistic look at native species, air and water quality, amount of catastrophic fire, lost homes, and firefighter fatalities, you see that things are in dire straits. There’s an increasing number of species proposed for listing, and we know that fire suppression, roads, and other factors have a cumulative negative effect for native systems, as well as threats to lives and property.”
“The answer is not to spend time analyzing what we did wrong, but spend time understanding our native systems and how Native Americans lived with fire in their native environment. They used fire for protection, and to maintain habitats. By learning from them and our native heritage, we can do the same. Fortunately, there’s now a move in the direction of working with, rather than against, our native systems.”
