Imagine you’re a school librarian - perhaps you are a school librarian - gazing lovingly at a shelf of freshly unpacked fiction books. Clean covers with pristine pages; it’s exciting having new stories to read and to tell.

Then think of the paper they’re printed on, the mills that made the paper, the wood pulp from which it came and the trees that used to stand tall.

Then think of the orang-utans swinging from the trees - until men armed with chainsaws come in the dead of night and chop them down. Men who sell the timber and use the money to buy guns to commit even more murderous raids.

In Sumatra and Borneo it can be as bad as that. “Conflict logging”, as it’s known in the trade, funds the activities of warring gangs and endangers the lives of orang-utans and other creatures. Eighty per cent of the logging there is illegal, with no regard to ownership or to the people and animals dependent on these ancient habitats. Within a decade, orang-utans could become extinct in the wild.

“Even the Indonesian government is saying, ‘Don’t buy our timber’,” says Alison Kennedy, production director at Egmont Press. She may not look like an eco-warrior, but her tenacity in chasing supply chains of virgin fibre and creating an audited system for grading paper is being hailed as a revolution in ethical publishing.

“If people can’t tell us where their wood comes from, we can’t buy it. We don’t want to publish a single book on paper that comes from illegal sources,” says Ms Kennedy, whose company produces 18 million of the 250 million children’s books printed worldwide every year. Within five years, she says, Egmont intends that all its titles, including adult fiction, will use only “green” paper.

“To get all unknown and unwanted material out of your supply chain without an ongoing cost is a real achievement,” says Martin Annis, a production technologist at WH Smith, echoing the cheers that have come from Greenpeace’s Book Campaign.

Egmont’s new paper procurement policy depends on an audited “chain of custody” receiving a certificate of approval from the Forest Stewardship Council, similar to the Soil Association’s stamp on organic food. Last month, the FSC logo appeared for the first time on both the cover and text paper of a new edition of Kensuke’s Kingdom, a novel by former children’s laureate Michael Morpurgo.

To celebrate the achievement, Egmont wants author and paper producer to meet. Which is why we are in Munkedal, in south-west Sweden, as guests of Arctic, a specialist paper company that is committed to eco-friendly practices. The first winter’s snow has just fallen and Morpurgo is still excited by four snow leopards he saw last night at a wildlife sanctuary sponsored by Arctic. (“You can go to the Himalayas and not see one!”) Wearing his customary black beret, he tours the mill with gusto, alongside his wife Clare and granddaughter Lea, who is on a gap year. Posing for the photographer on huge rolls of fresh paper, he exclaims at the heat the process generates, and how this is used to warm incoming cold water. “It’s a great adventure,” he pronounces. “What I’m learning is that these people have a passion for making paper this way, and they are uncynical and open about it.”

Later, we visit Arctic’s environmental centre beside the salmon-rich River Orekil, which supplies the vast quantities of water required. Drinks are served from neat bottles labelled “H20”, the water cleansed by a series of outdoor ponds and reed beds at the end of the paper-making process. Tastes fine, we decide, somewhat surprised.

For 40 years, Arctic’s mill has been working to improve its environmental record, minimising emissions in water and air, noise and waste, as well as strictly monitoring the sources of wood pulp. In the 1960s, we’re told, the mill had pretty much poisoned the Gullmar Fjord into which the Orekil flows.

Eva-lina Petersson, a customer services manager who grew up passing the Munkedal mill on her way to school, is proud that the environmental impact is falling year by year. “Now in the summer we can go fishing for mackerel in the fjord and take our children swimming. Locally they know the mill is clean and we feel good about it.” All Arctic’s staff are training for an environmental “driving licence”, learning the cleanest ways to make paper.

“I used to think a book is a book is a book,” says Morpurgo, whose links to the environment are evident through his charitable trust Farms for City Children, which gives holidays in the country to school parties. “I knew trees were cut down, but I also knew lots of trees were planted.”

He has only recently discovered the harm that books can do to the environment through practices such as conflict logging. “Potentially, Egmont’s new policy is the most exciting thing that’s happened in children’s publishing for a very long time,” he says.

For him, there is a delightful logic in Kensuke’s Kingdom being the title chosen by Egmont. It is a story of survival, about a boy stranded on a desert island discovering that he must share it with an old Japanese soldier. “There is conflict between them, but they find a way of living together. It’s all about harmony between people and generations, between us and nature,” he says.

Now the book (which has already sold 525,000 copies worldwide in 27 different languages and is being made into a film) fits the story and “any child, parent or grandparent can walk into a shop and choose a book that is guaranteed not to do damage”.

“It’s not often that the health of the environment and the health of children’s minds and publishers’ pockets coincides,” he says with a smile.

“It all makes sense doesn’t it?”

Kensuke’s Kingdom is published by Egmont Press, pound;4.99