If you have an accident, or hit a rock sticking up in the road, the whole car can catch on fire.
Even more rare, but it happens, the batteries can catch on fire with no accident.
logging roads and other roads in the boonies can be very rough, stressing everything in a vehicle.
Humans can accidentally start fires many ways, such as generating sparks, electrical, heat, a cigarette or match carelessly dropped, a glass bottle concentrating the rays from the sun, a camp fire, etc.
When it's real dry, better to just postpone activities in the woods, on dry grass, even the back yard and do other stuff.
Besides, if you are in the real boonies, you could get caught in a fire started by someone or something else and have no way to escape. The road I was on in northern NH is a dead end road with no clearings or other places to escape a fire.
Had one started below me, I'd have been screwed.
One more reason to just stay out of such places for a while.
Humans can accidentally start fires many ways, such as generating sparks, electrical, heat, a cigarette or match carelessly dropped, a glass bottle concentrating the rays from the sun, a camp fire, etc- - -
As a Boy Scout, I cannot remember ever starting a fire with a spark or friction bow. Maybe made smoke with a magnifying glass.
I did see it done by instructors.
But, yes, sparks and stuff can start fires.