Last week I met several university students who, much to my surprise, told me that they were only interested in non-fiction reading. That may be a little extreme, but for them and for those of you who are willing at least to alternate such books with the latest Tom Clancy time-waster, here are three outstanding natural history books to take along on your summer vacation.

    Linda Lear's biography, Rachel Carson: Witness for Nature (Henry Holt), should be required reading for everyone. Rachel Carson combined superb writing skill with broad scientific awareness gained from years as a government analyst and interpreter of biological information to take on the scientific establishment with an indictment of chemical pesticides in her 1962 book, Silent Spring.

    Few young people know and most older folks have forgotten that Carson had earned a reputation as the premier natural history writer of her time with Under the Sea Wind (1941), The Sea Around Us (1951) and The Edge of the Sea (1955) before, when deeply ill with cancer and beset by family problems, she wrote Silent Spring. Lear reminds us of that history and she also recounts the response to Carson's final book by a scientific community ill-prepared to accept the accusations, no matter how well based, of an outsider -- and a female to boot. Lear has done an excellent job of capturing the life of this extraordinary woman.

    Whether you own a cottage and are plagued with interlopers or you seek access to the countryside as one of those interlopers, you will gain deep understanding from Trespassing: An Inquiry into the Private Ownership of Land (Addison Wesley) by John Hanson Mitchell. Mitchell earlier won the John Burroughs Essay Award and you can well understand that honor when you read this book.

    The author centers his wide-ranging discussion around his walks through a three square mile tract of Massachusetts land originally deeded to a small tribe of Indians who had converted to Christianity. During the brief 1675 Indian uprising known as King Philip's War -- King Philip led the Pokanoket raid on the colonial village of Wamesit -- these "praying Indians" were removed from this land and herded onto an island detention camp. Later, one of the tribe members, Sarah Doublett, gave the property to Concord colonists with whom she was then living. This tortuous history leaves questions today about entitlement to this property.

    Mitchell uses this hook to discuss a remarkable range of aspects of land ownership from early British law establishing the commons to contemporary Supreme Court "takings" decisions.

    This book is perfect for summer reading. Because it is episodic, you can read sections between swims or hikes. At each sitting you will find much to entertain -- the author's wry humor is infectious -- as well as instruct you, a quite remarkable achievement with a subject that you would expect to be dry as dust.

    David Backes' award winning The Wilderness Within: The Life of Sigurd F. Olson (University of Minnesota Press) is of special interest to me because it is about the man who led one of the early battles to retain the pristine quality of the Minnesota Boundary Waters where I will be canoeing when this column appears. But Olson was also described by Interior Secretary Stewart Udall as "the nation's most eloquent and knowledgeable advocate for the protection of wilderness and wild rivers." I once carried Olson's The Singing Wilderness on a canoe trip and this year I will have this biography along to share passages with my companions. Those who portage carrying backpacks know that this represents high praise.

    I will have more to say about the issues raised in these three books in future columns.