Managing with Fire

Because of weather conditions and forest composition, the large destructive fires that occur in the west are not possible in our preserves. Instead of highly combustible resinous pine trees, our woods are populated with broadleaf deciduous trees, whose fallen leaves provide much less flammable fuel. In fact, the flames in our woodland burns are often low enough that an individual could simply step over them. That there are dozens of wildfires in Cook County preserves yearly that are safely contained illustrates the difference. Because controlled burns eliminate dried leaves and other fuel sources, they help protect the preserves from wild fires.

That said, many safety measures are taken when planning and conducting controlled burns. District personnel, like municipal firemen, must go through training and certification before they can plan, ignite, and execute a controlled burn. Trained District personnel survey the target site and create a detailed plan of action called a “Burn Plan” which monitors weather conditions (wind direction and speed, humidity, temperature), and the number of personnel and types of fire equipment needed to conduct the burn safely. Trained personnel conduct the burn, with the fire equipment to safely complete the burn. Local fire, police and other agencies and organizations are notified before and after the burns.

Smoke management is also carefully considered when choosing a location and conducting a burn. Local weather conditions are checked constantly before and during a planned burn to minimize smoke drifting toward adjacent neighborhoods.

On a smaller scale, brushpiles created during management workdays are often burned as they are made. This is the most efficient way of handling the woody debris, although the brush may be chipped by Forest Preserve District crews when the work is close enough to a street or bike path. The same careful planning goes into burning brushpiles. They are sited a safe distance from buildings or streets, and trained personnel and equipment are on hand. Local fire, police and other agencies and organizations are notified before and after brushpile burns.

According to the Illinois Environmental Protection Agency, the vast majority of air pollution from wood smoke comes from wood burning fireplaces, with prescribed burns contributing less than a hundredth of a percent. Even that last miniscule amount is offset by stimulating the growth of vegetation, which helps reduce pollution during the summer months, when air pollution is greatest.

Controlled burns are regularly conducted safely by conservation organizations throughout our region, including surrounding county forest preserve districts, the Chicago Park District, the Nature Conservancy, the Chicago Botanic Garden, Brookfield Zoo, The Illinois Department of Natural Resources, the US Forest Service at Midewin and many others. In many cases, these controlled burns occur in areas that are surrounded by homes, buildings and streets, without incident.