By Gabi Morey and Krisite Borchers
Wildfire is a natural component to almost any ecosystem. Like floods, hurricanes and avalanches, it has always been around. It is these types of forces that make natural changes to our ecosystems. Although fast-moving, crown fires that are so common today can be extremely damaging to both wildlife habitat and human structures, these types of fires have not always been the norm.
Since the retreat of the glaciers 10,000 years ago, both humans and lightning have caused fires. Ancient and historical people would light fires in the landscape for many reasons: to herd animals, to open travel routes, to create habitats and to encourage the growth of edible plants. These frequent fires created a diverse habitat for wildlife – trees of various ages, species and limited densities.
Ponderosa pine forests, for example, traditionally burned every three to 47 years. This created forests with open stands – much fewer trees per acre than we find today in our forests, fewer lower branches and more open meadows. When fires did occur, they burned out quickly and encountered more fire breaks. However, fire was also a threat to human settlements and merchantable timber. By the early 1890s, fire-suppression techniques were well underway, creating the forests we know today.
Somewhat unbeknownst to the ancients and the settlers, both the natural and human-made fires of yesteryear were actually very beneficial to the ecosystems where they occurred. Fire returns nutrients to the soil, opens up the canopy so new vegetation growth can occur and removes fuels on the forest floor so they don’t accumulate and create more catastrophic wildfires. The fires that used to occur were varied – sometimes they were low and cool, sometimes they were very hot. These types of fires formed a mosaic landscape, creating a more diverse habitat for wildlife, and areas where firebreaks occurred naturally, stopping fires before they spread too far.
In order for fire to occur anywhere, three components are needed – fuel, oxygen and heat. This is called the fire triangle. In a forest, fuel would include items such as dead leaves, grasses and downed woody debris on the ground. The heat source can be anything from lightning to cigarette sparks.
In the past 20 years, fire-suppression techniques have changed. We now have a better understanding of fire ecology and the environmental impacts of suppression on natural and human-made communities. Many land-management agencies and private landowners now even set prescribed burns to their land, attempting to replicate the frequency and benefits of historical fires.
However, as progress has been made, other problems are occurring. As human populations grow, our habitation in the wildland-urban interface has increased, bringing more homes into possible wildfire danger zones as seen in the current Durango fire, the 416 Fire. This, in turn, has brought on more of a need for education about wildfire to the general public, and how to protect homes and other structures. Luckily, groups such as Firewise help homeowners, community planners and others learn how to protect their homes from wildfires. More about Firewise can be found at www.firewise.org. Locally, visit southwestcoloradofires.org.
At San Juan Mountains Association, our hearts go out to all those affected negatively by the current wildfires. One can see why the San Juan National Forest has decided to go into Stage 3 status, which closes the forest for a period of time.