Wildland fires are an important ecosystem process throughout the western United States. Coniferous forests have long been subject to a frequent fire regime of low-intensity fires, which played an important role in reducing hazardous fuels and in rejuvenating the forests. In chaparral shrublands of California, high-intensity crown fires have been a strong force guiding the evolution of plant life, and regulator of ecological communities. In many desert habitats, fires have been far less frequent, and often are a more severe disturbance. Today the natural role of fire in these ecosystems is complicated by the fact that fire potentially favors plant invasions and these aliens in turn may alter fire regimes.
To restore more normal fire dynamics to a particular region, managers need to know how fire has historically affected the local system, and how it functions today. Researchers at the Western Ecological Research Center (WERC) are making contributions to this effort through detailed studies of fire history and fire ecology in the Sierra Nevada forests, California shrublands, and Mojave and Sonoran deserts. Knowledge from these studies are forming the basis for new policies aimed at restoring fire cycles that will present a lower risk to human life and property, and help safeguard the stability and diversity of Pacific Southwest ecosystems.