This fire primer is meant for decision makers concerned about forest fires in the American West. Using best science, we address seven fundamental questions related to the ecological importance of large fires and their appropriate management on public lands. Specifically, we examine: (1) what works best for reducing fire risks to homes and firefighters; (2) are large wildland fires an ecological catastrophe as claimed; (3) are fires increasing from historical levels; (4) does forest thinning reduce fire intensity or lower large fire occurrence; (5) how does post-fire logging affect forest rejuvenation and reburn intensity; (6) do insect outbreaks increase fire occurrence or intensity; and (7) how is climate change affecting fire behavior in the West?

The findings presented in this primer are based on hundreds of studies of forest fires in the American West and elsewhere as presented in “The Ecological Importance of Mixed-Severity Fires: Nature’s Phoenix” published by Elsevier, a world-leading provider of scientific, technical and medical information products and services. This primer is particularly timely given the recent passage of HR 2647 in the House and interest in the Senate on fire legislation. The primer is based on best available science on ways for communities to co-exist safely with fire’s ecological role on public lands, given fire is not going away, no matter how hard mangers try to suppress it.

Key Findings

• There are proven ways to coexist with fire in the backcountry by focusing on riskreduction measures in the home-ignition zone (within 100–200 feet from homes).
• A new forest naturally regenerating after a large fire is as ecologically valuable as an old-growth forest and is resilient to future fires. Post-fire logging, tree planting, and herbicides set back forest renewal, raise fire hazards, and increase the risk of uncharacteristically severe future fires.
• Thinning cannot stop large fires burning under severe fire-weather conditions that will increasingly occur as the climate changes in places. Thinned stands must encounter a fire when fuels are at their lowest levels post-treatment (only 5–8% chance) and under average fire-weather. Restoration should focus on priority areas to allow fires to burn safely in the backcountry.
• Insect outbreaks do not contribute to large severe fires and may lower future fire intensity as tree densities and tree crowns are actually reduced by outbreaks.
• Large fires produce much less carbon dioxide emissions than deforestation and fossil fuel burning, and new forests rapidly begin to sequester carbon, as vegetation grows.
• Large and severe fires were always historically prevalent, as they are today, and large severe fires are actually at an historical low and not at a recent surplus.