American Scientist

EVERGREEN: The Trees That Shaped America. Trent Preszler. 224 pp. Algonquin, 2025. $29.

Forest trees and human history are forever intertwined, and that’s as true for America as it is for the rest of the world. Trees simultaneously represent refuge, wilderness, commodity, and livelihood. They are at once time-traveling sentinels that function on unimaginable temporal scales as well as organisms that serve as landmarks for navigation of our own lives. Some of us have a tree that has a fond place in our thoughts and memories, others have had experiences with ancient trees older than the U.S. Constitution, or with seedlings and saplings we have planted, representing hope for an imagined future. 

Recent history of humans and forests in America also shows how trees and the forests they define have endured a strange and variable symbiosis with humans. If we could see a time lapse of the American relationship with trees, we would see forests across the continent ebbing and flowing as humans have liquidated and replanted landscapes, introduced exotic species and pathogens, sparked wildfires, and allowed prairies and agricultural fields to turn green with advancing seedlings. Forest products industries have risen and fallen alongside these changes. At the same time, climate change, megafires, new technologies, and scientific discoveries continually reshape the story of humans and forest trees.

Trent Preszler’s new book Evergreen: The Trees that Shaped America places a wide swath of American history in the context of evergreen trees, and Christmas trees in particular. Preszler writes, “But in the end, this is a book about the many wonders of Christmas trees, the kinds of wonders that are only deepened by knowing.” The book is more than that, however.

The Christmas tree offers many Americans a direct, tangible link between their appreciation of trees and the consumer culture that surrounds them. Preszler states,

To go from the prehistoric ancestor of evergreens, Archaeopteris, to a glitter-flocked, Bluetooth-equipped, perfume-spritzed plastic tree is to leave this world on a journey of forgetting where we came from. But forgetting, or not knowing in the first place, is exactly what the holiday industrial complex expects of us. For if we could see the truth about our festive customs, we would almost certainly change the way we celebrate. . . . how we shop largely determines our role in this world and what will become of it.

In this context, the Christmas tree is a symbol for modern interactions with nature. Of course, other trees could work too—nearly everyone has a type of tree they can connect to—but the Christmas tree serves as a recognizable gateway. A full book on just Christmas trees might have a limited audience, but Preszler rapidly expands the narrative. There are many evergreen species of tree in America, not just Christmas trees, and from pines to spruces, firs, hemlocks, and redwoods, there is a lot to explore. Nearly all have stories related to deforestation trends, and many are undergoing new threats in the face of climate change and disease.

Preszler explains how evergreen conifer trees have played a foundational role in the American experience, from the American Revolution to modern environmental dilemmas. They have formed the basis of economies and wartime technologies, they have been fuel for stoves and lamps, symbols for wilderness, and natural forest cathedrals in America that rival human architecture in other parts of the world. Although Preszler covers wide swaths of historical ground when it comes to evergreens, he also does something more: He makes a direct tie between various American cultures, evergreen trees, and the uncertain futures we face. He writes, “To understand America, start with the Evergreen.”

Preszler makes the case that the role of evergreen forests and trees in shaping American society is undeniable. Whether he’s writing about the Pilgrims viewing the evergreen trees as a “well-spring of prosperity,” dissecting the history of the lumber industry, or examining contemporary deforestation and ecological destruction, it’s clear how much of American history is intertwined with the history of evergreens.

In recent years, there have been a variety of books exploring interactions between people and trees, both fiction and nonfiction. In the presence of a wide variety of modern books on trees, might we ask, What use is another? Perhaps a tree-related analogy provides the answer. Back in 1966, the future president Ronald Reagan famously said, “A tree is a tree, how many more do you need to look at?” This quip was paraphrased as, “If you’ve seen one tree, you’ve seen them all.” Visitation rates to famous trees and forests show people clearly disagree—more than 5 million people annually visit redwoods in Northern California, giant sequoia trees in the southern Sierras, and old-growth trees in Olympic National Park alone. These statistics don’t count meaningful visits to other national parks, landmarks, notable trees, personal favorites, decorative trees (such as the Christmas tree) and the undeniable role that forests play in global regulation of global water and carbon cycles. If Preszler’s book arrives at a time when there is a virtual forest of other tree books, it also stands out as a unique and interesting reflection on trees and American society. Choosing one tree to represent all American interactions with forests is a difficult task, but finding the significance in a tree you have chosen is worthwhile. Preszler helps walk the reader through one such journey in a meaningful way.