so how is lighting tress on fire beneficial as opposed to not lighting them on fire?
I’m assuming that you’re referring to controlled burns. Forest fires happen naturally, and are a good way to clear dead leaves and brush on the ground. If people intervene and stop these natural fires immediately, the dead leaves will continue to pile up on the ground, and will make the next fire even bigger, more intense, and harder to contain. For that reason, some people believe that we should do controlled burns, which is when forests are purposefully set on fire to clear this brush and dead material in a way where the people in charge of the burn can make sure they are completely in control of the fire, and can stop it when it has fulfilled its purpose.
Lighting trees on fire releases the nutrients found in the trees through the form of ash. This will also prevent more fires from forming later on as fires cannot form in burned areas.