Forest fires increase carbon dioxide levels in the atmosphere, contributing to the greenhouse effect and climate change. In addition, ashes destroy much of the nutrients and erode the soil, causing flooding and landslides.

Fire has long been used as a tool to fertilize soils and control plant growth, but it can also substantially change vegetation, enhance soil erosion and even cause desertification of previously productive areas. Indeed fire is now regarded by some as the seventh soil-forming factor.

The biggest effect wildfire has on wildlife habitat is by altering the three things animals need most: food, water, and shelter. Tender understory plants and shrubs that provide food are lost, and this loss often results in wildlife moving away to areas where food, water, and shelter are more readily available.

The major cause of forest fires in the United States is human activities. Around 80% of forest fires in the United States are caused by humans. Most fires that are started by natural causes are started by lightning. Other natural causes include volcanic eruptions and sparks from falling rocks.

Wildfires threaten lives directly, and wildfire smoke can affect us all. They spread air pollution not only nearby, but thousands of miles away—causing breathing difficulties in even healthy individuals, not to mention children, older adults and those with heart disease, diabetes, asthma, COPD and other lung diseases.

Extensive fire damage to trees can significantly alter the timber supply, both through a short-term glut from timber salvage and a longer-term decline while the trees regrow. Water supplies can be degraded by post-fire erosion and stream sedimentation, but the volume flowing from the burned area may increase.

Wildfires can occur anywhere, but are common in the forested areas of the United States and Canada. They are also susceptible in many places around the world, including much of the vegetated areas of Australia as well as in the Western Cape of South Africa.

Forest fires always start by one of two ways – 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.

Slash and burn fires are set every day to destroy large sections of forests. Of course, these forests don’t just remove trees; they kill and displace wildlife, alter water cycles and soil fertility, and endanger the lives and livelihoods of local communities. They also can rage out of control.