The Burning Desire to Burn - Prevention vs. Prescription
By Wally Akins
What happened to the days when burning your property was an accepted practice and something that seemed like a part of life? When most everyone around the countryside burned? When neighbors helped neighbors burn their property? When you used nothing more to stop the fire than a cedar or pine sapling, or simply let it burn to the creek or road?
Native Americans burned some of our forests regularly, possibly every year or two. Studies of the southern and central Appalachian Mountains, including parts of Tennessee, show widespread fires burned about once every seven years from the mid-1700s until the early- to mid-1900s.
Obviously, society has changed and populations have grown to the point that using fire in a haphazard way is no longer acceptable, or even legal, in some circumstances. Closer neighbors, larger highways, people being uncomfortable with fire, the liabilities and legalities that lie within, all contribute to the fact that fire today is used very little relative to its use years ago. In fact, the absence of fire across our landscape has contributed to major changes in our forest health, appearance, and condition.
Tree establishment rates and species composition, as well as structural changes in forest stands, have occurred. Since the first half of the 20th century, forests with tree species that are shade-tolerant and fire-intolerant have replaced tree species that are adapted to repeated fires, such as pine and oak.
The fire suppression era began sometime during the late 1930s or early 1940s when a policy of widespread fire suppression was introduced and human-ignited fires were greatly reduced. One of the main reasons for this, but certainly not the only reason, occurred when Americans were presented with Smokey the Bear and those all too familiar words, “Only you can prevent forest fires.” These words enamored our society with the message that most forest fires are bad and detrimental to the environment.
Smokey the Bear is a product of the USDA Forest Service which organized the Cooperative Forest Fire Prevention (CFFP) program in 1942. It encouraged citizens nationwide to make a personal effort to prevent forest fires. This effort was a product of pending war, organizing our society in support of the effort to protect valuable trees which were a primary commodity for battleships, gunstocks, and packing crates for military transport.
After World War II, the focus of Smokey's campaign broadened to appeal to children as well as adults. In 1965, when Smokey's image evolved into the one we know today, the fire prevention concept developed into an industry of collectibles and educational materials in every shape and form imaginable, such as stamps, posters, magazines and radio ads. Even wristwatches portrayed Smokey and his slogan. Today, the internet and other forms of social media are being used in their highest form.
There are some who suggest that we have eliminated fire to the point that it is hurting forest management and stockpiling fuels for a future fire disaster. Evidence of this statement’s authenticity was apparent with 2016’s unprecedented and unforgettable fire season. Furthermore, most people see the present-day forests, however, modified by human intervention as they may be, as "natural," while at the same time believing that fire is unnatural.
Fire prevention should still be a critical component of the equation but total fire suppression is a misconception that forest ecologists have been trying to correct for years. Since the 1990s and early 2000s even the Smokey the Bear campaign has shifted to something more educational. In Smokey’s famous campaign slogan the words “forest fires” have been changed to “wildfires” and slowly, over time, our ecological correctness has been steadily improving. Society is becoming slightly more comfortable with fire. Over the last 10 years, acres permitted to be burned by the Tennessee Division of Forestry have increased from over 47,000 acres in 2005 to over 88,000 acres burned in 2016. Obviously, we in Tennessee are using fire somewhere.
Why would you want to use fire on your property in the first place and what is exactly meant by the words “controlled burn?” “Wildfires” are simply any unwanted or unplanned fires that burn in forests and other wildlands, such as shrub or grass communities. They are a powerful force that must be understood in order to control. Furthermore, most wildfires nationwide are caused by humans and can be prevented. “Prescribed fire” or “controlled fire” is the controlled application of fire to the land to accomplish specific land management goals. Ignitions may occur naturally or be intentionally produced. As timber demand and harvest have declined, only fire can provide landscape-level diversity for an otherwise unbroken static-aged Appalachian forest landscape.
The relationship between fire and biodiversity is complex and there are many factors to consider before you burn. The frequency, intensity, and season of fire are second only to precipitation in terms of vegetation response. Fire is not a onetime tool, it is a management program. One year of fire will not change years of fire suppression. Conversely, depending on the objectives of the landowner, repeated use of fire can help mold the land to whatever the landowner’s goals may be. By using the appropriate fire frequency and intensity, under proper environmental conditions, the native plant community can be maintained as a forest, woodland, a savanna, shrubland, or grassland.
Many plants and animals require fire for their survival, yet all wildlife are not affected equally by fire. Even in fire-prone ecosystems, some species and communities are highly sensitive to fire with fire being good for some wildlife and not good for others.
Generally, fire frequency at a 2 to 7-year return interval benefits a wide variety of wildlife by providing a diverse structure in the understory, increasing browse, forage and soft mast. The fire also creates snags and cavities for den and nesting sites. Fire intensity should generally below to limit damage to mature hardwoods. However, in closed-canopy forests, intensity should be sufficient to kill a portion of the large trees to allow increased sunlight into the forest floor. This stimulates and fosters growth below the trees which benefits wildlife.
Recent studies in the central hardwoods and the southern Appalachians illustrate the fire effects on different species of wildlife. Specific fire management recommendations for some of these species are as follows.
Bats: Moderate-to high-intensity dormant season (February-March) fire may be used to create snags, improve foraging, and increase day-roost sites. Low-intensity dormant or early growing season (mid-April) fire once every 5 to 7 years, can reduce the tree's midstory component in the forest and improve foraging conditions.
Reptiles: Dormant season burning encourages suitable vegetation structure, cover, and microclimate for lizards and snakes. Litter removal favors lizards and reducing tree overstory creates basking sites for these animals. Large scale, early-growing season (April) fire poses risks to some snakes as they’ve just emerged from their winter dens.
Amphibians: Dormant season (February-March) burning avoids harming salamanders as they are more active during the early growing season. Drier site conditions, which are the result of burns and/or timber harvesting, may reduce the abundance or activity of amphibians.
Songbirds: Forest songbirds that require a developed understory for nesting and foraging, such as black-and-white warbler, Kentucky warbler, hooded warbler, or eastern towhee, require low-intensity fire once every 5 to 7 years between August and March. Burning closed-canopy forests is unlikely to improve conditions for these birds unless the intensity is sufficient to kill some overstory, which could obviously damage timber. Forest stands should have a broken canopy, allowing at least 20 % sunlight to the forest floor or sufficient understory structure may not develop. For open-canopy, woodland birds which either nest in tree cavities or at least 3 to 10 ft. aboveground, a dormant (February-March) and growing-season (September-early October) fire every 6 to 7 years can be used to retain a desirable stand structure.
Deer: In mature, moderately-open, hardwood stands, a low-intensity dormant (February-March) and growing-season (September-early October) fire every 3 to 5 years can be used to stimulate forage if the canopy is thin enough. In closed-canopy forest stands, the same may provide some increase in forage availability, but the increase may be negligible. For early successional openings, a low to moderate intensity fire maintains forage availability and cover for fawning. Importantly, most burns should be conducted outside the fawning season (May-July).
Grouse: In mature, moderately open woods with 20-40 percent sunlight, a low-intensity, dormant-season (February-March) fire once every 6 to 8 years maintains desirable stem density and understory cover. In a young forest with no tree overstory, fires with moderate-intensity during the dormant season, once every 15 to 20 years usually maintains stand composition and structure in an optimum condition. If grouse is a focal species, avoid early growing-season (mid-April -early June) burning, especially if burn units are large as the grouse re-nesting rate is very low.
Turkey: In mature, moderately open hardwood forest, a low-intensity fire once every 3 to 5 years will likely maintain a suitable understory structure for nesting and brood rearing. No negative population-level effects have been reported for nesting and brood-rearing season (April- early June).
Northern Bobwhite: In early successional openings and oak savannas, a late dormant-season (February-March) and growing-season (September-early October) fire every 2 to 4 years is required. Early growing-season (April-May) fire has little direct effect on the peak nesting period (June-July) for these birds. Late growing-season (September-October) fire helps control woody composition, but burn areas should be small, less than 30 acres, unless the fire is low-intensity and patchy. Burning at this time of year may reduce woody cover available in winter, which has been identified as a major limiting factor for quail.
All in all, the right fire, at the right place, at the right time, can accomplish your land management objectives. If you have never used fire on your property, try to familiarize yourself with this management activity and the many benefits it provides. As mentioned above, fire is complex. It should be respected, used cautiously and with diligence, but when used correctly the changes to the land will be fascinating. Find someone who does use fire and tag along. Furthermore, there are many different ways to become more educated about the fire. Tennessee Wildlife Resources Agency, Tennessee Division of Forestry, Tennessee Prescribed Fire Council, Southern Blue Ridge Fire Learning Network, and many other agencies and organizations have websites and other resources available to educate landowners about the benefits and uses of fire.
Wally Akins now serves as the Wildlife Program Manager in TWRA Region III. He previously served as the region’s small game biologist and assisted in prescribed burning and shortleaf pine restoration projects across the region on public and private lands.