It is true. If they are planned correctly forests fires can be very beneficial to the environment. Controlled fires are fires that are set on purpose in order to burn away material that could be harmful later. They are carefully watched by firefighters to makes sure that they don't get out of hand. Controlled fires burn away ground litter that is potentially flammable.
Fire sweeps through ground litter.
Small amounts of ground litter reduce the risk for large-scale, uncontrolled fires. Burning also manages the vegetation in a way that can enhance the productivity and the diversity of animals and plants. It helps maintain and restore failing ecosystems. By burning dead or troublesome plants, there is room for native plans to grow. It creates attractive habitats for animals and other plants to migrate into and add to the ecosystems.