I have a couple questions- I don't burn pellets. I do use them as litter in my rabbits' litter boxes (great, cheap, compostable). It seems that they make them from a consistent tree species. I normally get Energex from my local hardware store (Benson's, Londonderry). If they switch tree species, it follows that the heat output and ash amount would change. How do they get a consistent source? Does anyone have a link to their tree harvest methods and replacement? Just curious.