N A T URE’S NATURE’S FURY FOREST FIRE Anita Ganeri
N A T URE’S What Is a Forest Fire What Is a Forest Fire The sight of a fire sweeping furiously through a forest is both frightening and spectacular Forest fires also called wildfires are devastating events Their intense heat burns leaves and branches to a crisp before making them explode roaring and crackling into flames Giant flames leap hundreds of feet into the air along with columns of thick black smoke In the biggest fires spinning tornadoes are created by the rapidly rising heat Flames raging through a coniferous forest in Yosemite National Park in California A fiery path Even the biggest forest fire starts as a tiny spark If the vegetation is dry enough the spark quickly grows into an inferno Flames spread in all directions burning everything in 4
N A T URE’S their path They damage and kill trees incinerate plants on the forest floor and even kill roots underground Buildings in the way are also burned Any unfortunate people or animals who become trapped between the fast-moving flames may be killed by smoke When the flames are gone a charred smoking wasteland is left behind Firefighters do not attempt to put out intense forest fires Instead they try to stop the fires from spreading and allow the flames to burn themselves out Where and why Forest fires happen in places where hot summer weather dries out dense vegetation They happen more often during droughts The dry vegetation catches fire very easily allowing the fire to spread rapidly Fire affects both coniferous forests and deciduous forests It can also burn across grasslands scrub and brush Most forest fires are started accidentally by people but some are started naturally by lightning A NATURAL CYCLE Lightning has been starting forest fires throughout history Layers of charcoal in rocks tell us that there were devastating fires millions of years ago Blackened tree rings in very old trees show that natural forest fires are regular events in some places Although forest fires can be very damaging they are not always bad news Fire clears out old trees and allows new ones to grow There is a natural cycle of fire and regrowth In fact some species of trees could not survive without regular fires Scientists cutting a slice from a giant sequoia tree The tree rings will tell them when forest fires happened in the past W h a t i s a F o r e s t F i r e 5
