Brief History By Environmental Historian Stephen J. Pyne

Causes of fire in Fir Forest

Environmental historian Stephen J. Pyne, in his book ‘Brief History’, suggests that fire and flame can only exist on earth in the presence of the carbon based "living world". Our carbon based and flammable environment supplies all of the elements of chemistry for the creation of fire.

The two major causes of Forest fires - naturally caused or human caused. Natural fires are generally started by lightning, with a very small percentage started by spontaneous combustion of dry fuel such as sawdust and leaves. On the other hand, human-caused fires can be due to any number of reasons. This includes smoking, recreation, improper waste dump and shifting cultivation in Bhutan. Human-caused fires constitute the greater percentage

Lightning randomly strikes the earth an average of 100 times each second or 3 billion times every year and has caused some of the most notable wild land fire disasters in the western United States. The most frequent causes of natural wildfires are volcanoes, lightning, spontaneous combustion, and sparks caused by rockslides. Natural coal seam fires have also been attributed to causing wildfires when combustible plant material is located nearby.

Most lightning strikes occur in the North American southeast and southwest. Because they often occur in isolated locations with limited access, lightning fires burn more total acres than human-caused starts. The average 10-year total of U.S. wildfire acres burned and caused by humans is 1.9 million acres where 2.1 million acres burned are lightning caused.

Still, human fire activity is the primary cause of wildfires - having nearly ten times the start rate of natural starts. The average 10-year percent U.S. wildfire starts are 88% human caused and 12% lightning caused. Wildfires are started by human negligence. Intentional arson, equipment sparks, discarded cigarettes, unattended campfires, controlled agricultural burns and power lines have all caused a number of wildfires in the

Forest Fire in Fir vegetation (source: www.forestryimage.org)

A wildfire is defined as being an uncontrolled fire that occurs in the wilderness. They can be massive in size and have the ability to spread across vast distances, jumping rivers, roads and fire breaks in the process. Usually, wildfires occur in hot and dry climates.Wildfire is a part of nature. It plays a key role in shaping ecosystems by serving as an agent of renewal and change. But fire can be deadly, destroying homes, wildlife habitat and timber, and polluting the air with emissions harmful to human health. Fire also releases carbon dioxide- a key greenhouse gas—into the atmosphere.

Wildfires can serve to clean up any dead or decaying matter strewn across forest, which, in turn, enables an increase in new plant growth. Wildfires are also useful in maintaining the balance within an ecosystem by removing any harmful insects and disease plants. An added benefit of plant removal is an increase in sunlight, which can assist in the regeneration of plant seeds. Scientists have also realized that wildfires can increase the amount of plant and animal diversity within a particular ecosystem. In the midst of a wildfire, exceptional amount of nutrients are released into the soil, which can result in a flood of new plant growth. Some plants even require wildfires to germinate their seeds and stimulate growth, such as the peculiar species of Panderosa pine