Prescribed Fire and Smoke Management


Nearly 100 years of fire suppression, historic logging and grazing practices have dramatically altered forest conditions. The exclusion of more frequent, low-intensity fires has resulted in a huge accumulation of flammable vegetation and woody debris in eastern Washington forests. One consequence has been a steady increase in large, uncontrollable wildfires which burn very large forest areas, threaten rural homes and communities, expose residents to choking smoke for many days, and seriously damage tourism-based economies.


In response to these trends, the US Forest Service has pursued a dry forest management strategy on the Okanogan and Wenatchee National Forests for more than a decade. The goal is to achieve more sustainable conditions in these forest types where fire is a frequent visitor. “Sustainable conditions” translate into more natural, park-like stands composed of relatively fire tolerant tree species such as Ponderosa pine, Douglas fir and western larch. The primary management activities necessary to achieve those objectives include thinning (reducing the number of trees) in dense forest groves and prescribed or controlled burning. The thinning is often done with commercial timber sales to alter species composition and reduce the amount of excess fuels. Prescribed fire is then used to further reduce logging slash and remaining excess natural fuel as well as encourage the growth of desirable native plants. The result is a forest where wildfires are likely to be much less severe. These areas of reduced fuels also provide firefighters with better opportunities to successfully halt wildfires before they threaten rural communities and valuable resources.

Current Situation

In an effort to balance the undesirable effects of smoke in the air and the benefits of landscape-scale fuels reduction, the Forest Service and the Department of Natural Resources plan to coordinate on selected prescribed fire projects in excess of 1,000 acres. The purpose is to validate the conditions necessary to conduct large-scale burning projects without impacting human health and public acceptance. A thorough notification effort will focus on local public education, understanding and acceptance.

More Time Needed

Because of the magnitude of the fuels problem on national forest lands in eastern Washington, Forest Service fire managers see a need for larger prescribed fires and occasional multiple day, landscape prescribed burns on a thousand acres and more at a time. Once such a burn has begun, there may be no cost effective way to shut it down before fuels within the fire lines are consumed.

Under provisions of the federal Clean Air Act and state law, the Washington Department of Natural Resources (DNR) is responsible for approval of forest management burning. The department monitors weather conditions and forecasts to guide its decisions whether burning will meet air quality standards. The greater the quantity of material burned, the greater the potential threats to air quality. This project is designed to help identify improved methods for accurately predicting and avoiding smoke impacts for large-scale burns.

Frequently Asked Questions

Why do we do Prescribed Burns?
Site Preparation/Regeneration: Before a logged area is re-planted it might be burned to reduce the slash (branches and other debris). Burning returns nutrients to the soil and lets more sunlight get to the ground which helps the planted seedlings survive and grow. Burning can also help natural regeneration of plants.

Fuel and Risk Reduction: Carefully controlled burning can help reduce unnatural concentrations of fuel that might lead to catastrophic wildfires.

Re-introducing Fire: Fire is a natural part of the forest ecosystem. Without it the forest becomes unhealthy. For the last 70 years, most natural fires have been put out. Prescribed burning is a way of getting fire back into the natural cycles of the ecosystem.

How is it Done?
Prescribed burns must undergo environment effects analysis that includes public participation. The project then must have a detailed implementation plan prepared that describes the desired outcomes, the methods to be employed, acceptable fuel and weather conditions and contingencies for unexpected events.

With approval from DNR smoke managers, crews may execute the plan when conditions are favorable. Most involve use of a driptorch (a hand-held canister that drips burning fuel). Crew members walk across an area to ignite the fire in a pattern that will produce the desired results. For larger areas, helicopters are sometimes used to ignite prescribed fires from the air. This speeds up the process and decreases safety concerns for ground-based personnel. Regardless of the tools employed, the pattern and timing of the ignition help determine the nature of the fire that results.

What About the Smoke?
The goal is always to have prescribed fires burn quickly, cleanly, and under control. Smoke should be carried up and away from the area. Conditions are watched constantly. Many times scheduled burns are cancelled at the last minute if things aren’t right for meeting that goal. But weather and winds are unpredictable and there is always a chance that smoke will end up in the valleys. This happens mostly at night when cool, calm air settles and collects in the low areas, bringing smoke with it. This event is referred to as an inversion which is very predictable, but the intensity is not. Burn managers must decide whether or not the benefit of burning out weighs the short term affect of the inversion. Burning is curtailed if the inversion is predicted to be strong and long lasting.

Smoke is an unavoidable consequence of prescribed burning. But fire is an essential part of the natural cycles and health of the forest.

Natural fuels burning projects which re-introduce fire into the ecosystem may cover 1,000-acres or more. Due to their size, they are likely to burn longer and produce smoke for a week or longer.

Prescribed Burn Approval Process

1. The Department of Natural Resources is responsible for regulating air quality emissions from forestry burning.

2. A DNR Air Quality Specialist in Olympia evaluates conditions and determines whether to grant approval for proposed burning.

3. That decision is posted on the DNR website —

4. The smoke approval is still subject to review by the Prescribed Fire Manager at the burn location to assure the necessary resources and conditions for a successful mission are present. In many cases, data collected at the burn location is fed to the National Weather Service whose meteorologists prepare a site-specific (“spot”) weather forecast to provide detailed information. Using this and actual fire behavior observations, ongoing decisions are made about how much of the approved acreage should be burned each day. At any point, the Fire Manager can choose to suspend burning operations until more favorable conditions return.

Up-To-Date Information

To track burning activities daily you can go to the (Incident Information System) website and review burn area maps, photos and burn status.