Prescribed Fire for Conservation of Natural Resources
By Dr. JT Pynne, Wildlife Biologist.
Photo by JT Pynne
Forest Fire Introduction
When most people think of fire on the landscape, they immediately think of huge western wildfires which are extremely severe and intense. Intensity and severity are two common terms used to describe fire behavior and effects, respectively. Western fires are often very intense, with large flames that consume trees entirely, and very severe, meaning they consume a lot of fuel in the area, which causes extreme damage to the landscape, infrastructure, and even human lives. In many areas in the U.S., fuel has built up over time due to fire suppression, which results in fires with higher intensity and more severity. More recently, climate change is resulting in hotter temperatures, longer droughts, and larger fires which also contribute to severity and intensity of fires and decrease forests’ ability to recover.
However, fires are not always so intense or severe that they damage forests and threaten infrastructure. On the contrary, fires of lesser severity and intensity are important for ecosystem health, species diversity, and wildlife habitat, and can actually help landowners manage their land, rather than being a threat to it.
Fires Are a Natural Part of Forest Ecology
The natural world has been dealing with fire for millennia because it is a natural occurrence. “Dealing with” fire means that plants and animals have adapted to fire. Fires consume plants as fuel, so many of them have adapted to survive. Fires lead to higher biodiversity of resilient plants that actually require the disturbance. We can think of fire’s relationship with these plants as a cycle (called a positive feedback loop). Fire “weeds out” less resilient plants, but provides bare ground for colonization by resilient species. Fires also cycle nutrients back into the soil, so the plants that put more energy into developing their root systems get nutrients like carbon and phosphorus as they are cycled through the fire feedback loop.
Fires affect wildlife too, mostly for the better. Animals have also evolved alongside fire. When fire approaches, animals know how to escape, emigrate, or hideout underground. Those diverse and resilient plants are important for wildlife because herbivores and omnivores need a wide variety of forage, and predators need those herbivores well-fed for sustenance. Fire disturbance leads to increases in both forage quality and forage diversity. The increase in forage diversity leads to increased insect diversity, since many species of insects depend on specific species to complete their life cycles. Increased plant diversity also in the understory creates more food for pollinators, and increased insect populations provide food for many other wildlife species.
Photo by JT Pynne
Western Wildfires vs Southern Forest Fires
Almost every ecosystem on Earth has experienced fire in its geologic history. The frequency of fires, however, is variable and is dependent on land cover and structure. For example, the giant sequoias may experience stand-replacing fires every couple hundred years on smaller scales, when all of the trees in that particular stand are consumed and then new sprouts can potentially grow. Conversely, southeastern U.S. pine forests can tolerate fire every year. In general, several smaller scale fires occurring spottily across the landscape is more aligned with the North American historical fire regimes. Fires were caused by lighting and lit by native tribes. Indigenous people started fires for wildlife management, agriculture, to clear areas for buildings, and several other reasons.
Reasons for Using Prescribed Fires
Why would we continue to utilize and work alongside fire? That’s easy: It provides several benefits. First, prescribed fire is a helpful land management tool. Land managers can conduct prescribed fires – controlled burns that land managers ignite under a controlled weather and safety prescription – to manage the land without much equipment or need for herbicides. Having barriers that do not carry fire like roads, dozer lines, disked soil, or rivers and streams, is important within that prescription.
Second, prescribed fires help reduce fuel in forests, so that when accidental or lightning-caused fires do occur, they are less severe and intense and more easily contained. Instead of burning out of control, damaging the soil and killing even fire resistant plants, and possibly spreading to nearby land causing damage to structures or livestock, accidental or lightning-caused fires that start on fire-managed land can be easily stopped by backfires. Therefore, prescribed burning both protects forest health and reduces potential loss of life and property on nearby land.
Third, prescribed fires increase biodiversity and wildlife habitat through mechanisms outlined above. This effect of fire is well-documented in the scientific literature. More plants and more animals are present in areas that are frequently burned. For example, longleaf pine ecosystems require a fire every 1-3 years to maintain more than 100 different plant species in any given 1 square meter. The increase in flora increases value to fauna as well. Other southern pine forests are adapted to frequent fires as well – the loblolly/shortleaf pine ecosystems of the Piedmont also support higher flora and fauna diversity when burned frequently. In the North Georgia mountains, fire is necessary to create habitat for Ruffed Grouse. Burned pine and hardwood forests produce large quantities of seeds for Wild Turkey and Northern Bobwhite, palatable forage for white-tailed deer and eastern spotted skunks, and more dense forbs for eastern cottontail and fox squirrel cover, to name a few examples.
Photo by JT Pynne
There are several resources for landowners or land managers to begin working with fire to benefit natural resources. First, get in contact with your local Georgia Forestry Commission (GFC) office and learn about the resources available. GFC issues permits for managers conducting prescribed fires, as long as the weather is safe. GFC has prescription plans where managers fill out size and location or burn, goals, fuel characteristics, safety information, fire-specific weather conditions, and several other factors that are necessary to know before ignition. In Georgia, having this plan and a permit from GFC decreases liability risk substantially. Also, contact a private lands biologist with Georgia Wildlife Federation, Georgia Department of Natural Resources, or another organization to get plans for wildlife and forestry management.
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