Most paper is made from wood, and below emails there is often a “footer” asking us not to print out the message unless we really need to, in order not to waste wood. Of course any waste is reprehensible, but fortunately wood is not a finite resource like oil or coal. There are 4 billion hectares of forest in the world — see the entry “Global forest cover” in the book — and the total annual consumption of fuelwood and industrial roundwood is 3.5 billion cubic metres (m3), i.e. 3.5 / 4 = 0.9 m3/ha. The average annual wood yield from forests can be a lot higher than that. Even in the relatively cool climate of Europe it can exceed 30 m3/ha/year, and in high-rainfall subtropical areas it can be even higher, although the global average will of course be much lower than 30.

Mikael Grut, 10.10.2014