With each passing dry season, it seems headlines about devastating wildfires are becoming increasingly commonplace. In 2012, such blazes consumed an acreage equivalent to the combined size of Massachusetts and Connecticut. This year has likewise proved to be exceptionally devastating in many regards. You've likely heard conversations about the Rim Fire -- California's fourth-largest wildfire ever, burning a total of 260,000 acres -- or the Yarnell Fire, a tragedy that claimed the lives of 19 firefighters in Arizona.
After hearing about these events time and time again, one might develop questions that most articles on the topic fail to address. Why do wildfires continue year after year? Can't we do something to better manage fires? To further compound matters, wildfire reports or news segments are likely to include terms the majority of us are unfamiliar with -- making these questions that much more difficult to answer.
Of course, questions like the above are also long-standing; wildfires have been happening for as long as lightning and forests have been around. But to be clear, the ways in which wildfires impact us are evolving. Here are five key facts to understanding wildfires in today's ecosystems:
1. Wildfires are a natural occurrence, but they're changing.
Though many wildfires are caused by human carelessness or sparks from machinery, much of the land burned annually can be traced to lightning strikes or the sun's heat. These fires can, when properly managed, actually be beneficial to forest ecosystems. However, a number of factors -- including decades of fire suppression, 'invasive species' like cheatgrass (a highly flammable plant taking hold in the American west) and the habitat range expansion of pine bark beetles (which kill off trees that then drop their parched needles on our forest floors) -- are changing the frequency and intensity of these natural fire cycles. Together with climate change (which is resulting in drier summers and more intense storms that can trigger lightning strikes in many parts of the country), these factors are creating wildfires that are stronger, hotter and more unpredictable.
2. Land recovers from wildfires, but slowly -- and it often needs help.
It will take years for some of the scarred land affected by the Rim Fire to regenerate naturally, and some may never do so without our help. Generally speaking, if a wildfire is too hot, tree roots and seeds buried deeply in the soil can be killed. If damage caused by a wildfire reaches this extent, restoration -- a process in which ecologists, land managers or other professionals are tasked with replanting and stabilizing a natural area -- is needed.
3. When replanting, some methods are smarter than others.
Landowners, both public and private, need to be careful about restoration efforts in order to keep out harmful invasive species. Ongoing studies in regions across the world are uncovering the best plants to introduce to a region post-wildfire. For example, Chicago Botanic Garden scientist Dr. Andrea Kramer is working to bolster restoration efforts at the site of last year's Pine Ridge Fire in Grand Junction, Colorado. Dr. Kramer's research is testing certain plant species that could potentially replace the seeds currently being used for restoration.
4. Reintroducing native plants helps to maintain healthy landscapes.
Early findings from Dr. Kramer's research show that certain 'native plants' -- or those plants that have occurred naturally for many years in a given area -- likely outperform the seed mixes traditionally used by local restoration efforts in several important ways. For example, data show some native plants (we call them 'native winners') are better at growing quickly and reducing soil erosion after fires. Perhaps more importantly, these native winners might be the key to keeping out the non-native invasive species, like cheatgrass (mentioned above), that make wildlands more prone to uncontrollable wildfires. Native winners' performance in these indicators makes them better candidates for restoration. Properly managed, they can help break the cycle of wildfires escalating out of control.
5. There is hope that the future will have "better" wildfires.
Many organizations are working together to ensure future fires on our public and private lands, especially in the American West, will be "better." That is, we're working toward prescribing and managing natural fires so they are healthy for the land without compromising future forest health or harming human communities.
Much can be written on the science of wildfires, and indeed much has been. Still, knowing the above facts will help you better understand the issues surrounding wildfires. Should the above statements have created an appetite for further understanding, Paul Tullis' recent feature in The New York Times Magazine explores the debate on wildfire suppression through the lens of the latest advancements in fire science.
As we move deeper into fall, we hope to hear of fewer and fewer wildfires. And as research continues, we are confident that the passionate experts who have dedicated their careers to this work will make great strides in mitigating wildfires and restoring healthy ecosystems.