Prescribed burning
Overview
Prescribed fire is fire applied in a knowledgeable manner to forest fuels on a specific land area under selected weather conditions to accomplish predetermined, well-defined management objectives. Also known as controlled burning, prescribed fire is widely used in forest management, farming, prairie restoration and other agricultural facets. Burning has many benefits for farming and soil composition, as well as in the fields of ecology and conservation. Today in the United States all state owned land management agencies, including private landowners, use prescribed fire as a tool to achieve certain natural recourse conditions.
History
Prescribed fire has been used for thousands of years, and is thought to have begun during the Neolithic age (new stone age) at the beginnings of agriculture[1]. People would burn fields to make for better farming areas and increase the mineral make-up of the soil2.
Native Americans have known about and reaped the benefits of controlled burning since well before the 16th century. It was used to provide access to dense forests, make for easier hunting and produce land more suitable for farming. European settlers recognized these advantages to burning and continued to implement prescribed fire. This burning procedure would reduce the amount of forest fuels that accumulated and sometimes create out of hand destructive wildfires, which often led to property damage.
Eventually, an increase in tree planting and a growing urban environment in the early 20th century led to foresters advocating for the eradication of fire from forests entirely[2]. However, it became apparent that the exclusion of prescribed fire all together was not an option. Following many severe forest fires, United States foresters began to use controlled burning again.
Benefits
Effects on Trees
Prescribed fire has a vast number of benefits for an environment. One of the most recognizable is the reduction of harmful forest fuels that can accumulate rapidly. This accumulation can lead to very serious wildfires that have potential to harm communities and ecosystems. Areas treated systematically with prescribed fire are much easier to manage when wildfire does occur.
Controlled burning is useful in preparing land for a new seeding and/or planting, as well as the natural regeneration of trees in a forest. Fire creates and exposes natural mineral rich soil and limits the amount of competing vegetation during the periods of planting and seeding. In areas used to grow pines, low-value, poor quality, shade tolerant hardwoods often occupy or encroach upon land best suited to growing. Unwanted species may crowd out or suppress pine seedlings. In most cases the total destruction of the understory vegetation is neither practical nor wanted. With the careful use of prescribed fire however, the understory level can be managed to limit the amount of competition these trees must face with desired species.
Effects of Animals
Animals often have very positive reactions to the use of prescribed fire[3]. Controlled burning is highly recommended by many state forestry commissions for wildlife conservation when certain conditions take place. Periodic fire tends to favor understory species that require a more open habitat. A mixture of burned and unburned areas maximizes the edge effect, promoting a vast and varied population of wildlife.
Fire affects many birds nesting and feeding practices positively. However, overall reaction to the burning has differing affects on birds of different species, with different feeding and nesting strategies. Bark insectivore species, such as the woodpecker, tend to see the most positive influence following a controlled burn, and are often sighted in areas following a burn more than in pre-burn or control areas. Other insectivore species of bird undergo positive change when fire is introduced to the environment, such as aerial insectivores whose hunting strategies are better implemented by the decrease in forest debris, making it easier to perform maneuvers while in the air.
Fires lead to the production of snags, which are very important nesting and food sites for many bird species. Though fire does destroy snags, the continued and systematic use of fire in an area is shown to reduce the number of snags lost to fire and increase the numbers of those produced[3].
Pest Control
Controlled burning has an important role in the prevention and control of disease and insects. Burning typically can kill off harmful insects such as cone beetles, who usually reside on the grounds of forests, and can have great negative impacts. Intentional fire has been known to aid in the control of parasitic fungi that live on trees and often hinder growth, without always killing the tree itself.
Uses in Forestry
The forestry industry relies heavily on the uses of fire to clear out understory vegetation, making logging of mature trees much easier and possible.
Harmful Effects
Though prescribed fire has many advantages, there are also many harmful effects that sometime occur with its use. Slash-and-burn, a technique that has been used for thousands of years, often destroys large areas of land and causes severe erosion and deforestation[4]. This can lead to plots of land that are often then unsuitable for farming, the intention of the process, as all of the nutrients have been eroded away. Slash-and-burn is now usually associated with tropical areas and rainforests, and its overuse is leading to the destruction of many valuable forest habitats[4].
Prescribed fire when performed improperly can often have negative effects. At times, the burning will be more severe then planned, leading to incredible destruction and the unwanted felling of trees. A mistake when factoring environmental condition can lead to the smoking out of roads and highways, making it very dangerous for drivers and other people in the area if the smoke is inhaled.
References
- ↑ 1. Georgia. What is Prescribed Fire?. , 2010. Web. 29 Oct 2010. <http://www.gfc.state.ga.us/ForestFire/PrescribedBurn
- ↑ 2. Virginia. Virginia Prescribed Fire Council. , 2010. Web. 29 Oct 2010. <http://www.dof.virginia.gov/fire/vpfc.htm>.
- ↑ 3.0 3.1 3. Farris, Kerry L., Steve Zack, Andrew J. Amacher, and Jennifer C. Pierson. 2010. "Microhabitat Selection of Bark-Foraging Birds in Response to Fire and Fire Surrogate Treatments." Forest Science 56, no. 1: 100. TOC Plus, EBSCOhost (accessed October 8, 2010).
- ↑ 4.0 4.1 4. Joseph D. Cornell (Lead Author);Michelle Miller (Topic Editor) . "Slash and burn". Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [First published in the Encyclopedia of Earth January 31, 2007; Last revised Date January 31, 2007; Retrieved October 29, 2010 <http://www.eoearth.org/article/Slash_and_burn>