Over the last week, I have been helping conduct prescribed burns on the prairies at Dyck Arboretum as well as for some area landowners. This annual spring ritual for me is one of the most engaging examples of our mission – cultivating transformative relationships between people and the land.
For thousands of years since the last ice age, prairie has evolved with fire, an essential element of disturbance that maintains prairie as prairie. Without fire, readily available seeds of trees and shrubs will invade and turn prairie into forest within decades. Gone are the days when lightning or Native American-set fires regularly kept this element of maintenance in place every few years. Today, landowners, ranchers, and land managers must regularly be the starters of fire. A few years ago, I blogged more in depth about why we should Embrace Prairie Burning.
Conducting A Safe Burn
I cannot sufficiently instruct one to conduct a prescribed burn in a short blog post, but I will summarize the important elements to be considered when making fire go where you want it go. Conducting a safe prescribed burn is in actuality a simple process, but one MUST adhere to strict guidelines regarding 1) relative humidity, and 2) wind speed. When relative humidity (RH) is at 80%, fire is very difficult to start and when it is at 20%, fire is very difficult to put out. Making sure that the start and end time of the burn stay within those parameters is paramount, and sunlight and temperature have a profound effect on RH. With every 20-degree F increase, RH drops in half.
Wind speeds between 5-15 miles per hour (mph) are important too. Below 5 mph, winds can be shifty, unpredictable and dangerous when trying to control fire. And it probably goes without saying, but winds over 15 mph can easily carry flames where you don’t want them to go. A 911 dispatcher will not allow a burn to start if wind gusts are above 15 mph, anyway.
There are three types of fire we regularly refer to in prescribed burning. A back fire works directly against the wind, a flank fire works perpendicular to the wind, and a head fire is pushed with the wind.
The intensity of these three fire types is from low to high, respectively, as is their ease of control. To most easily contain a fire within a particular burn unit, we start with downwind back fires until a sufficient black line is established, work around to flank fires until those flanks are made safe, and then finish with a head fire to most quickly finish the burn once all the boundaries have been sufficiently secured. The following diagram, shows the general progression of a prescribed burn, otherwise known as the ring fire technique.
Important tools in managing fire include those that help you quickly move fire and those that help you quickly put it out. In the past, I used a drip torch full of a diesel/gas mixture, but have more recently relied on the much simpler (and lighter) tool of a garden rake for dragging fire. My favorite water carrying device is a water backpack and hand pump with support of extra water in a larger water tank carried by our new Hustler MDV. The backpack with a 5-gallon capacity can get heavy and cumbersome, but it sprays a reliable 10-15′ stream of water and is easily the most mobile and useful tool I know for carrying water and putting out fire.
Strengthening A Human Connection to the Land
The act of burning a prairie brings together the four classical elements (earth, air, fire and water). The earth produces prairie vegetation, and in spring time, the prairie is renewed after it combusts when brought together with air and fire. We use water to bring this process to a conclusion. As I stated above, people are essential to keeping this positive feedback loop going today.
The people who are essential to this stewardship process of prescribed burning include my colleagues, volunteers willing to lend a hand, and the landowners themselves who initiate the process. All of these individuals make up an important community of people strengthening a connection to the land.
The identity of Kansas is built around the native landscape of the prairie and fire will always be a part of that identity. While the implementation of prescribed burns may be a laborious task that can make my body feel old, it is an important ritual that keeps my spirit young.
One of my favorite experiences of conducting a prescribed burn is often found in the final moments of such an event. Once the final head fire has been lit and the hard work is complete, there are a few moments to enjoy the sounds of crackling flames of moisture-laden grasses and the happy sounds of mating boreal chorus frogs in the background.
In the video below, I leave you with the magical sights and sounds of this experience.
An important disturbance mechanism for prairie ecosystem health, a restoration ritual that connects a Kansan to its native landscape, and a series of sights, sounds and smells that both comforts and stirs heightened senses – prairie burning in the spring represents all these things to me.
Ever since participating in my first prairie burns during graduate school in Wisconsin, where I was trained to safely conduct prescribed burns, I have held a great reverence and respect for this process of igniting the prairie. Prairies and a whole array of plants and animals became adapted to semi-regular lightning-set fires on the Central North American Plains since the last ice age approximately 10,000 years ago.
In the last couple of thousand years, humans have also been important vectors for bringing fire to the prairie and helping determine its geographic extent on the landscape. Native Americans used fire to clear safe zones for lodging, attract or direct wildlife for food, and celebrate cultural rituals. Their actions helped extend prairie further east into areas that have since reverted back to oak-hickory forests, as the Native American presence and their fire rituals were extinguished. European ranchers on the Plains hold a similar respect for fire and use it to help fatten cattle and control invading woody plants that would eventually shade out prairie grasses.
Prairie fires in Kansas have been met with resistance. Increased human habitation and careless use of fire in untamed wild places puts residences more at risk and created an understandable fear of fire. Air quality problems affecting human health, due mostly to automobiles, power generation and industry in major metropolitan areas like Kansas City and most recently Wichita, are certainly not helped by spring prairie burns. Wildlife managers can cite that annual prairie burns in the Flint Hills have become too frequent for the success of grassland birds, including greater prairie chickens that require some residual cover for adequate foraging and nesting success.
Kansas has a rich history intertwined with the prairie and Kansans embrace prairie as an important part of our cultural and natural history, our recreation through eco-tourism (state park use, hunting, fishing, birding, hiking, etc.) and our economy (ranching). Where prairie has been removed, it has left behind a legacy of some of the best agricultural soils in the world. While mowing does provide some of the benefits of fire, it does not provide all of them, and is more costly and time-consuming. We must find ways to utilize and implement prairie burning with greater safety, intelligence, and purpose.
Simply put, a culture that values prairie must also value fire.