I was a heavy equipment operator for a small town about 25 years ago or so. One of my jobs was, about once a month, I’d take the backhoe to where the street department dumped the wood chips from grinding up trees and such. I’d spend a few days there turning all the piles to keep them from bursting into flames as they went through their heat. It amazed me at how hot that stuff would be when I’d dig into it good. Steam would poor out of it.