Actually they did something like slash and burn agriculture, but they apparently rotated sites, allowing forest regeneration.
they also maintained cattle? i dont think 3 million people would have used only 3% of the forest area if their main diet was bovine heavy.
Which is extremely common in native traditions pretty much around the world. Aboriginals from Australia have a concept of "cool fires" and Californians famously had very careful "cultural burns". Fires were always carefully managed not to burn too hot and kill seeds