Five of us went to Florida on spring break. We stopped off in Tennessee on the way back and bought a few hundred $ worth of fireworks. One summer night, we decided to go road drinking and bring the fireworks along for entertainment.
We stopped on a ridge overlooking a creek with several hundred acres of woods beyond the creek. It seemed like a perfect place to launch some bottle rockets. One of the bottle rockets landed in a birds nest or whatever and caught fire, setting most of the forest ablaze.
We left thinking that it would hopefully burn itself out, since it would be impossible for a fire department to get to the blaze, and rain was in the forecast.
My friend's dad (on the volunteer fire department) explained to his family at breakfast the next morning how the F.D. was called out to a forest fire. The F.D. couldn't get to the blaze, and couldn't figure out how it started. My friend didn't offer any ideas.
We all went back to the scene the following night, and several acres of trees / brush were still smoldering.