Trees are crops. They grow, they are harvested, they are replanted, and they grow again. Like corn, only it takes longer. There are Christmas tree farms here where hills are covered with trees in various stages of growth, designed so that one section is always mature when Christmas rolls around. They won't run out of Christmas trees.

Properly managed forestry does not "use up" a forest.

A tree makes solar energy into wood. After the oil runs out, there will still be trees. After all the uranium is mined, there will still be trees. There were trees when our ancestors had tails, and after we have been extinct for ten million years, there will still be trees. There will be trees until the sun cools off to the point where they can't grow any more.

They don't use old-growth redwood for a bonfire. In fact, they used white oak, red oak, hard elm and hackberry. The pollutants emitted by the fire are lost in the noise compared to pollutants from many other sources*, and are also considered to be "biomass" pollutants by environmentalists, which are different from those emitted by fossil fuels when considering global warming issues.

There may be safety reasons not to have a bonfire of this type, but not environmental ones. Have fun, guys, and be careful out there.

*Particularly countless acres of "protected" forests that burned like tinder this past summer.