<Tr> <Td> Recovered fibres </Td> <Td> 147.0 </Td> </Tr> <Tr> <Td> Total pulp </Td> <Td> 334.0 </Td> </Tr> <P> Most pulp mills use good forest management practices in harvesting trees to ensure that they have a sustainable source of raw materials . One of the major complaints about harvesting wood for pulp mills is that it reduces the biodiversity of the harvested forest . Pulp tree plantations account for 16 percent of world pulp production, old - growth forests 9 percent, and second - and third - and more generation forests account for the rest . Reforestation is practiced in most areas, so trees are a renewable resource . The FSC (Forest Stewardship Council), SFI (Sustainable Forestry Initiative), PEFC (Programme for the Endorsement of Forest Certification), and other bodies certify paper made from trees harvested according to guidelines meant to ensure good forestry practices . </P> <P> The number of trees consumed depends on whether mechanical processes or chemical processes are used . It has been estimated that based on a mixture of softwoods and hardwoods 12 metres (40 ft) tall and 15--20 centimetres (6--8 in) in diameter, it would take an average of 24 trees to produce 0.9 tonne (1 ton) of printing and writing paper, using the kraft process (chemical pulping). Mechanical pulping is about twice as efficient in using trees, since almost all of the wood is used to make fibre, therefore it takes about 12 trees to make 0.9 tonne (1 ton) of mechanical pulp or newsprint . </P>

Where does the wood for paper come from