The number of trees required depends on several factors, including the type of paper and the sizes of the tree and book. To estimate, an average tree provides approximately 8,333 sheets of copy-type paper. Using this formula, one tree can provide 16.6 copies of a 1,000-page book.
It is estimated that to publish all the printed books sold in the US annually requires 30 million trees. Over 160 publishers, representing 40% of the market share, have developed environmental policies or signed agreements related to responsible paper use. The growing prevalence of eBooks is also greatly reducing the use of trees.