Which activity is known to contribute to forest fires?

Discarding cigarettes is a significant activity that contributes to forest fires due to the potential for igniting dry vegetation. When a cigarette is carelessly tossed away, it can easily ignite grass, leaves, or other combustible materials found in forested areas, especially in dry conditions. Smoking materials are a common cause of human-induced wildfires because they can smolder and emit sparks without immediate detection, leading to ignition that can spread rapidly under the right conditions.

In contrast, planting trees, watering forest areas, and installing forest trails are activities aimed at forest management and conservation. These practices help maintain the health and vitality of forest ecosystems and typically do not pose a risk of starting fires. Therefore, discarding cigarettes stands out as a direct action that can lead to dangerous fire situations.