|How we use forests affects fire behavior
|The MISSOULIAN GUEST COLUMN, Wednesday, August 1, 2007
||By PETER KOLB, The MISSOULIAN GUEST COLUMN
As wildfires change, so should sensible policy.
The summer all forest managers and firefighters have been dreading is here. A wet spring resulting in ample grass growth followed by record heat a month earlier than normal, and our normal fire season should just be starting. Conditions are currently worse than in 1910, when more than 3 million acres burned across Idaho and Montana in what was called a national catastrophe. So what have we learned?
Historically, such bad fire years are not unprecedented. Climate reconstructions estimate that the average weather for Montana was hotter and drier for centuries at a time before 1600 A.D., when we slid into the mini-ice age. It is possible that all of Montana 's surface vegetation burned off frequently in conflagrations much larger than the fires of 1910.
Perhaps our climate is reverting to those conditions, either naturally or with the help of human-caused global warming. But as the vegetation burns, what about the people both historic and contemporary?
An increasing body of evidence, archaeological and cultural, indicates that this country's native inhabitants used fire extensively as a tool to survive. As they would migrate on their annual cycles, they would set fires and leave so that the following year dense forests would be cleared out and the grasses, forbs and shrubs they depended on for food would regenerate.
The majority of forests that greeted early settlers had been created by generations of human use. Since that time, human influences have continued to shape our forests, perhaps differently than before, but not necessarily all bad either. Early settlers harvested the big ponderosa pines that had been cultured by Native American burning and used them to build homes and barns in able to survive. These were your ancestors, without whom you would not be here.
An emerging industry paid the way for more people to live and thrive in Montana , although the life was not easy. A system of roads increased the ability of people to access the land, as well as to trade and sell their products. After all, the wood you use as paper or for your house has to come from somewhere.
At some point, people also recognized that the natural resources were not unlimited and conservation efforts came about. Trees were planted, grazing regulated better and the wildfires that consumed precious timber and grass were controlled. And these efforts were successful because everybody worked hard at them and universities studied and taught professionals how to implement them better.
Contemporary Montana probably has as much or more forest and better rangeland than at any time in the past 2,000 years, perhaps 10,000 years. The successes of good land management practices have left Montana as a highly desirable place to live, and have brought with it unprecedented population growth that wants to enjoy these resources, except when wildfires and smoke are not allowing them to. So who can we blame?
As the science shows, climatic conditions are the fundamental determinant of wildfires. As many have indicated, wildfires will occur across Montana much like earthquakes occur in the San Francisco Bay Area. However, there has been little or no distinction made between if wildfires occur, and how they occur.
The "how wildfires occur" issue has been and continues to be extensively studied for the construction of more comprehensive and accurate fire behavior models. It has been shown repeatedly through scientific studies and applied experience that forest structure and composition can have a very strong impact on how a wildfire burns.
But it is not that simple. Montana forests are complex mosaics of tree-dominated ecosystems, each of which has a different potential response to wildfires and forest cultural practices. Reducing tree density, surface fuel loading and fire ladders does reduce fire severity on most forest types under most weather conditions.
There are some exceptions. Increasing the diversity of tree species and structures across a landscape through progressive harvesting practices has also been shown to have a positive impact on reducing the extensiveness of severe wildfire effects.
Roads give firefighting teams a quicker response time and ability to suppress more than 90 percent of all wildfire starts. This is well documented. Forest management, like any agricultural management practice, can provide many positive impacts, and alternatively, if done incorrectly some negative impacts.
However, relying on the phobias generated by only publicizing the bad exceptions will not allow for the progressive adaptation of policy or land management practices. If the current climatic trends continue, a more active and adaptive forest management approach will be essential - not only to lessen wildfire impacts, but to help our forests survive drought, insect outbreaks and increased demands from the human population.
Wilderness areas are equally important, if for no other reason because they are the scientific control that shows us what the no-management alternative looks like.
But limiting management only to small zones around homes is like the dike around New Orleans ; it will only work against moderate events. Forest wildfires are a landscape phenomenon and must be treated as such for any hope of having an impact. Imagine the conditions of this summer becoming the average.
Wouldn't you want to do something to keep wildfires burning at low-severity levels on lands beyond your immediate fenceline?
Peter Kolb is a Montana State University extension forestry specialist with more than 20 years of experience researching forest ecology and disturbance processes in the Northwest.