How does the world work? Why is it the way it is?

Each of us goes through our daily lives guided by an intuitive set of answers to these questions. At some subconscious level, those who are more aware understand that their comprehension is of necessity incomplete. (I maintain that this realization is the source of intellectual curiosity—after all, those people who are most rigid in their insistence that the world is a certain way for reasons they can explain [such as “God’s law”] tend to be the most resistant to new knowledge.) For readers who want to fill some of those gaps in understanding, this book is a jewel—or, rather, a collection of jewels, revealed page by page.

Did you know that no one knows how many species of salamanders exist in a forest, because salamanders live in such restricted ranges that those on one side of a valley may be markedly different from those on the other side? Indeed, most salamanders spend their lives within a few square meters of forest floor, evolving and adapting to their tiny patch of earth, and so drawing into question the very idea of speciation.

Did you know that the reason the wood of hickory trees has a coarser grain than sugar maples’ has to do with the different economic calculations the trees have (unconsciously) made as they trade off protection against late spring freezes and maximizing the capture of available sunlight?

Did you know that shrews are so hyperactive that they cannot survive long above ground? Their fast breathing would dehydrate them to the point of death—they must breathe damp, subterranean air.

David George Maskell’s book is full of such revelations. He employs in the extreme a device that I have long appreciated as a writer and a reader: tell a large story by telling a small story. In the case of The Forest Unseen, he selects a tiny patch of old growth forest on a Tennessee hillside—a few square meters—and observes it meticulously over a calendar year. From this speck of woods he draws out threads that allow him to weave an ecosystem tapestry that stretches back into the ice ages and forward into an altered climate. His illumination of what we know is also an illumination of how much more we have to learn—and, critically, how little we understand. I have always mourned the loss of a forest when I pass a clearcut. Until reading this book, though, I did not understand how much the word “forest” contains.

Reading Maskell I am reminded of the work of another great naturalist writer, Bernd Heinrich. Both writers are able to bring their acute powers of observation to bear on the page in ways that are wondrous and revealing. You cannot read either man and see the world the same way afterwards. That is the mark of more than writing—that is art.