Certain areas burn with differing frequencies (naturally).
Eg, coast range burns every few centuries while cascades and sierras it is more like every other year.
Sorry for no references, so please have a large grain of salt with those stated frequencies. IIRC those are the tight order of magnitude. Though, we are also talking much smaller fires compared to the mega blades we see today that kills everything rather than rejuvenates. These fires today burn everything and down to 4 feet under the soil. It's a different beast.
Eg, coast range burns every few centuries while cascades and sierras it is more like every other year.
Sorry for no references, so please have a large grain of salt with those stated frequencies. IIRC those are the tight order of magnitude. Though, we are also talking much smaller fires compared to the mega blades we see today that kills everything rather than rejuvenates. These fires today burn everything and down to 4 feet under the soil. It's a different beast.