The Case For Thinning Our Forests

Across the American West, catastrophic wildfires have decimated the landscape —destroying homes and property, devastating soil, air and water quality and wiping out thousands of acres of irreplaceable wildlife habitat.

In the last three years, we have seen two of the worst wildfire seasons on record. In 2002 alone, four states—Arizona, Colorado, New Mexico and Oregon—had their biggest fires in history. Once again, anyone in his right mind is asking the same question: what can we do to stop these catastrophic wildfires from happening?

According to a recent study by the USDA Forest Service, there are four factors working together that have resulted in the type of unnatural wildfire we are now regularly seeing: weather, the abundance of fuel in our forests, lack of moisture and the terrain. Obviously, humans have no real control over the weather (including the lack of rain) or the terrain. So, logically, we need to focus on the one factor we do have control over—fuel buildup.

The fuels that feed and create these wildfires are dead and dying trees, in addition to smaller diameter trees that fill the gaps between large trees. Catastrophic wildfires most frequently occur when small, naturally-occurring fires spread from the ground vegetation (surface fuels), through the smaller trees (ladder fuels), into the canopies or crowns of the large trees. It is these crown fires that quickly rage out of control and do the most damage.

The Forest Service study clearly suggests that the most effective strategy to prevent crown fires is to use thinning, together with other treatments such as prescribed burning, to reduce surface and ladder fuels. This conclusion is corroborated by almost all professional foresters.

Another wildfire fuel source is dead and dying trees, the result of overgrown forests, where too many trees vie for limited water and soil nutrients. Without sufficient water and nutrients, trees become more susceptible to insect infestations and disease and eventually die. Dead trees create a dry, “tinder box” in the forest, a catastrophe waiting to happen. The solution, again, is thinning out the forests, allowing trees to get the amount of water and nutrients they need to remain healthy and fire-retardant.

Congress should pass the Healthy Forests Restoration Act which will allow more thinning to prevent catastrophic forest fires. There will be some who try to argue that thinning is not the answer. They should remember the four factors that are causing these catastrophic wildfires—and which one humans can control. Fuel reduction is the only answer; and the only way to do that is through thinning.