@mekkaokereke Can't find the source, since it's been a while I read it (might in a Jared Diamond book), but I remember it's well documented through dendrochronoly that for millenias forests burned regularly, effectively removing the undergrowth and preventing *massive* fires.
When people started building houses near/in forests, they started controlling fires more, and the undergrowth kept growing until it fueled more sporadic but bigger fires.