We are in the burn season, which occasions some thought on that part of prairie work.
It is somehow paradoxical to think that prairies depend upon burning. It is paradoxical because we think of us, homo sapiens, as outside of nature, or at least corrupters of nature, and that pure nature would do fine, if not better, without us. And what could be more purely "nature" than the north American prairie.
But prairies languish without the occasional burn. Last year's growth dies, and the year's growth before that is dead, and stays dead. New growth has to find it's way through the old growth. But the old growth in time becomes a thick mat, making it hard to navigate for many creatures, and making it hard for the new growth to make it's way through the old growth. Many times, Jeff and I will drive past a wetland or prairie and one of us will say "that could use a good burn."
Burning removes years, sometimes, decades, of duff, or accumulated dead matter. Such removal opens up the earth, allows it to breath, allows the sun to reach the earth, and thus gives the prairie new life. I am not sure what chemical and agronomic response takes place, but I can say that it has happened many times that we burned a languishing, thinly vegetated prairie one spring, only to come back two years later to burn again to find indicators that it flourished since the last burn.
The paradox is that prairies are as natural as nature in North America can provide, but they require burning, which requires humans. Indeed, the prairie co-evolved with humans, and depends upon humans to flourish.