Logging, thinning would not curtail wildfires

Guest Viewpoint


Logging, thinning would not curtail wildfires

By George Wuerthner

Published: Dec 26, 2008 09:26AM
Opinion: Editorials & Letters: Story

Kathy Lynn’s guest viewpoint in the Dec. 17 edition of The Register-­Guard about wildfires and protecting communities was full of flawed assumptions, and consequently flawed solutions.

Lynn correctly noted that acreage burned by wildfire has increased, but she implied that somehow this was a result of “unhealthy” forests — and her implied solution is more logging.

Unfortunately in ecology, what seems obvious is not always accurate. Remember, the sun does appear to go around the Earth.

Contrary to common opinion, large blazes are not driven primarily by fuels, but by climatic conditions. When you have high winds, high temperatures, low humidity and severe drought, you have the right ingredients for large fires.

Not surprisingly, the past decade has been a period of severe drought, high summer temperatures and low humidity. Those conditions have been coupled at times with high winds — so naturally we would expect more large blazes.

Such weather-driven blazes are unstoppable and go out only when the weather changes — not because of a lack of fuels.

Although we are seeing more charred acres in recent year, the idea that this trend is unnatural is skewed by our limited time perspective.

The years between 1940 and late 1980s were moister and cooler than, say, the turn of the century or in the past decade. Unfavorable conditions for fire ignitions kept the annual acreage of wildfires down to historically low levels.

However, if you go back even to the turn of the century, you will find that tens of millions of acres burned annually — including a single fire in Idaho and Montana that in 1910 charred more than 3.5 million acres. One researcher in California recently estimated that prior to 1850, an average of 5 million to 6 million acres burned annually in California alone.

Healthy ecosystems burn, and often burn by the tens of millions of acres. The spate of large wildfires we are experiencing now are not “abnormal” or an indication of “unhealthy” forest. Rather, we are seeing the natural response of a healthy forest ecosystem.

Given that wildfire was so common for thousands of years, it is not surprising that recent research shows that wildfires, particularly severe wildfires, increase biodiversity.

If anything, we probably need more wildfire, not less. With global warming we will probably get it, as vegetative communities adapt to new climatic realities.

Another surprising finding is that mechanical fuels treatment, commonly known as logging and thinning, typically has little effect on the spread of wildfires. In fact, in some cases, it can increase wildfires’ spread and severity by increasing the fine fuels on the ground (slash) and by opening the forest to greater wind and solar penetration, drying fuels faster than in unlogged forests.

Although we are really unable to stop fires, nor prevent their spread by logging and thinning, that doesn’t mean we need to let fire burn down homes.

Research by Jack Cohen at the Missoula Fire Lab in Montana has found that the most effective strategy for protecting homes and communities is accomplished by reducing the flammability of homes. Replacing wooden shingles with metal roofs, removing firewood from around a home, keeping gutters free of debris and other simple measures can significantly reduce the likelihood that a home will burn.

Logging the forests is not the answer to protecting our communities from wildfire, nor does the sun circle the Earth.

George Wuerthner is a part-time resident of Eugene. He is an ecologist, and the author of 34 books, including “Wildfire: A Century of Failed Forest Policy.