“Tis the season for conifers—whether they are grown decorated for a little Christmas cheer or simply serve as a bright, green contrast to their naked leafy counterparts.
What you may not appreciate is that conifers, which grow and thrive year-round along with other evergreens, have played an amazing role in the United States. story. Take Eastern white pine. It graced the first coins minted in the British colonies. Meanwhile, spruce loggers helped secure some key labor rights in the early 20th century, including the eight-hour day and overtime pay.
These stories and many more are told by Trent Presler, an environmental economist at Cornell University, in his new book. Evergreens: The Trees That Shaped America.
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Scientific American spoke with Presler to learn more about the book and the stories it tells.
[An edited transcript of the interview follows.]
How did this book come about?
I was buying a Christmas tree at a tree farm on Long Island, and there were rows of artificially colored fluorescent neon trees like Dr. Seuss – pink, purple, green and yellow – and they were selling like hot cakes. And I just thought, “What, isn't just a simple evergreen enough for us? Do we really have to turn it into this flashy commercial product?”
As I dug deeper, it became clear that I could probably come to understand the biography of America as seen through the lens of Christmas trees.
Which tree appeared before conifers? What was this ancient tree like and why is it still important today?
Archaeopteris dates back 367 million years and it was really forerunner of our modern trees. It was the first tree found in the fossil record to have the vascular structure we now see in trees with a rigid central trunk. It almost looked like a heavy Christmas tree with fern leaves on top.
They simply dominated the Earth's surface – and eventually led to the evolution of what we now know as evergreens. This line of descent is part of what gives evergreens such resilience. They developed in very harsh climatic conditions. thrives in places where almost nothing else grows.
But all these Archaeopteris the trees died, fell into anaerobic swamps and were compressed over millions of years into what we now know as coal. We feed our economy and American society with essentially dead, prehistoric Christmas trees.
The Pine Shilling was minted in Massachusetts in 1652.
Heritage Art/Heritage Images via Getty Images
Let's fast forward a little. How did conifers influence US history? Can you share some of your favorite stories?
One of my favorite stories is “The Pine Riot.” Britain first came to America because they ran out of trees. The British needed large, thick, strong pine trees to make masts for the Royal Navy, but they couldn't get them from the forests of Europe, so they sent pilgrims to America to cut down the trees and ship them back to Britain. Common mythology states that the Pilgrims were religious separatists, but in reality they were timber traders sent here to obtain timber for the Crown. But the colonists rebelled and beat the king's gamekeeper at a tavern in Wear, New Hampshire. This became known as the Pine Riot, which inspired the Boston Tea Party a year later.
Fast forward to World War I, and the Allies desperately needed pliable, strong, and fibrous wood to build airplanes. Fighter aircraft were just beginning their development, and the fuselages were made of wood. So the military mobilized a massive workforce of hundreds of thousands of troops who converged on the coasts of Oregon and Washington to harvest Sitka spruce, which they called plane spruce. And this really turned the tide of the war.
This touches on so many parts of our history – the good and the bad, the unusual, the wonderful and often the shocking.
A scene from a military logging camp in Washington State during World War I.
Heritage Art/Heritage Images via Getty Images
Tell us a little about the research that went into this book. How did you track down these stories about conifers?
It was a two-year journey. I traveled around the country, to about 20 states, visiting sawmills, forests, historical archives, and First Nations reservations. It was almost as if every time I found a story and continued that theme, there was more waiting for me. I learned a lot while working on this book, and it was a joy.
Do you have a favorite conifer?
I love Douglas fir. It's something quixotic and mysterious—it's not actually a fir, but botanists aren't quite sure how to classify it. It grows these ramrod-straight trunks with very hard wood. It is great for construction and this also led to its demise. This was very valuable to the construction industry, especially during the post-World War II housing boom when suburbs were essentially invented on Long Island. Douglas fir was the most readily available evergreen softwood at the time and became the primary wood for construction.
It would also make a very pretty Christmas tree. If collected young, up to 10 years old, it is still bushy and looks fluffy. If you let it grow for 50 to 100 years, it will simply be a giant tree that has no branches for the first 80 feet of the trunk. He transforms from adolescence to adulthood.
It's my favorite because it's on the edge: it's a deeply commercial and economically important material product for America's economy, but it also captivates us and holds our imagination in the lead-up to Christmas.
When it comes to Christmas trees specifically, what would you like more people to know about them?
I just think the healthiest and purest thing we can do before Christmas is take a real tree.
Over the last perhaps 20 years, the plastics industry has done a great job of marketing natural, real, living Christmas trees as bad for the environment. But real Christmas trees can do a lot of things. They give a local farmer a job. They often occupy areas of marginal, rather rocky soil unsuitable for growing other crops that might otherwise be turned into shopping centers, so they protect the American landscape. They are natural, completely biodegradable and return to the earth. And the Christmas tree farms themselves provide habitat for all kinds of wildlife, birds, other types of grasses and wildflowers.
What fun science fact about conifers would you share at a party?
What makes their wood so good for construction is that it has a different cellular structure than hardwoods. Maple or oak, if you look at them under a microscope, their wood is made up of millions of small cells that are round in shape and arranged in a chaotic mosaic. But the wood of evergreen conifers looks like LEGO bricks with those little rectangles lined up next to each other in that perfect lattice design. This is beautiful to me: their strength as wood is actually built right at the cellular level. I think it's fascinating.
