Wood

Nature performing her works... if you're interested there is some interesting reading to be had by googling "last old growth forests"...There are forests in Poland that have not been logged or "managed" or inhabited for over 500 years...amazing these places still exist...but they are disappearing fast... they are healthy and functioning just as the primordial forests did ...a riot of leaf mold, fungi, insects, animals, etc...keep the wheel turning... no need for mankind to help...