The vast majority of western dry forests are at risk of large, high-intensity fire because of the effects of poor forest management over the past century. The primary factors that lead to current forest conditions include logging large trees, fire suppression, and livestock grazing. Since the beginning of the 20th century, all three of these factors have been present in western forests, and they continue to play a role today.

Logging operations have historically removed the largest and most fire-resistant trees. The young trees that replace cut trees are highly susceptible to fire and serve as fire ladders, allowing the fire to reach up into the canopy of the forest. Because fire-suppression efforts have been intensive and have effectively removed fire as a thinning agent from most forests, many small trees that would have been killed by fire have been allowed to survive. Besides being prone to fire, these small trees are present at such high densities that their growth is slowed by intense competition.

The relatively frequent, low-intensity surface fires that historically burned in many forests were carried primarily by ground vegetation such as grasses. But livestock grazing on our public lands has severely reduced the amount of grasses, and fires are now able to burn only when there is significant buildup of woody debris, often leading to severe fires. By shading the ground, grasses would suppress the growth of tree seedlings at the youngest stages. With grasses reduced or cropped short by livestock, tree seedlings are much more likely to survive, growing at high density and encroaching on meadows and grasslands.


The Center has three objectives in terms of policy on fire in western forests, and we’re promoting these through our work on forest management in New Mexico and Arizona, our programs to curb urban sprawl in fast-growing regions like southern California, and elsewhere.

First, fire policy must provide wildland-urban interface communities with protection from the threat of forest fire. Second, it must be geared at reducing the severity of unnatural forest fires and reintroducing fire as a natural component of the ecosystem. Third, forests should be put on a trajectory toward recovery through the reintroduction and enhancement of a range of natural forest ecosystem processes. The Center’s highest priorities include protecting lives and houses in the communities that are currently at risk from forest fires. At the same time, it is critical to protect areas of special concern, such as municipal watersheds and reservoirs and habitat for sensitive species.

Photo by jmcphers/Flickr