Wood ignites at temperatures in the hundreds of degrees. How are some wildfires supposedly started by sunlight without human action or lightning?

Question

Wood ignites at temperatures in the hundreds of degrees. How are some wildfires supposedly started by sunlight without human action or lightning?

In: 1508

Answer 1

In short it’s not the wood starting the fire. There are however countless other sources that can ignite way sooner and so in fact ignite. Some are mentioned here. Decomposition can raise temperatures to the point of starting fire. Fungi and other things can ignite at way lower temperatures. And once they catch fire the reaction releases enough heat to start igniting actual wood.