How Many Trees Does It Take to Print a Bestseller?

Not long ago I published an article which detailed the best selling books and authors of all time. Using this information I have decided to estimate the size of forest that would have to be felled to print these books.

To do this I have to make some assumptions.

I assume that each title was produced in one print run. I do this to avoid the complications that arise if I considered the reuse of forests to produce latter editions. This assumtion has some merit for recent best sellers, such as the Harry Potter series or the Da Vinci Code because large sales volumes were produced very quickly.

The number of trees required to produce paper varies considerably depending upon the type and quality.  During the 1970s an environmental pressure group, Conservatree, popularised the view that a ton of recycled paper could save 17 trees. Their website explains how calculations have become more sophisticated since that time.  

1 tonne of office paper consumes 24 trees (or 1 tree makes 8,333 sheets of paper)

1 tonne of newsprint consumes 12 trees (or 1 tree makes 16,666 sheets of paper).

The calculation assumes that the paper is made from a mixture of hardwood and softwood trees 40ft high and 6 – 8 inches in diameter.

Modern best sellers tend to be produced on lower quality paper, so I intend to use the 12 tree per tonne figure. I am also going to assume that bestsellers are produced on paper that is one third of the size of office paper. This suggests that one tree makes 50,000 pages.

For convenience letters assume that the average bestseller is 500 pages long.

This leads to the statistic that 1 tree makes 1,000 books.

Many bestselling authors achieve sales of 20 million books. This requires a forest of 20,000 trees. Exceptional authors such as J.K Rowling and Dan Brown achieve sales of 400 million books. This requires a forest of 400,000 trees. These figures only consider the trees that are used for paper production. It does not include other trees that may need to be removed to access the useable wood.

Foresters compile statistics of forest prodcutivity. To proceed, I estimated that each 40ft high tree supplies 3.74 cubic metres of paper.  Then, I gathered statistics on the forest yield per hectare.  I found that the Congo rain forest is believed to have a sustainable yield of 15 cubic metres per hectare per year.  The release of a bestseller that sold 20 million copies per year would require the devoted resources of 5,000 hectares (or over 12,000 acres) of Congo forest.  This is about the size of 6,000 football or baseball grounds.  A greater acreage would be needed to achieve this output from slower growing forests. Put differently, the production of a 400 million copy blockbuster, a 20 million bestseller or 200 thrillers each selling 1 million copies on an annual sustainable basis would require the dedicsted resources of a forest the size of Hong Kong

Although this calculation is little more than an educated guess  it should introduce a topic for further discussion.