Growing Old Growth

My introductory environmental geography course concludes with an assignment that sends students to the archives of Sierra, the little-known magazine published by the better-known club. The magazine began as a monthly bulletin in 1893, just a year after John Muir started the organization; it was published as a glossy bimonthly magazine when I was most active in the Club back in the 1990s and continues as a quarterly magazine today -- online and in print. 

Amazingly, the archives are now available back to the January 1950 issue (much earlier than was the case even a few years ago). It serves as a rich trove of environmental journalism on all manner of topics related to the protection of land, air, and water.  

I learn a lot any time I browse those archives and I tell myself I should try to keep up with the current editions. I rarely find time to do either, however, so I an glad for the reports from my students, who invariably find articles I really need to read! 

The latest example is "The Future Is Old Growth" by Krista Langlois. 

Photo: Mitch Epstein via Sierra

I decided I needed to read the article when the student who reviewed it mentioned a quote from David Foster, who is the author of Thoreau's Country, one of the books I use in an upper-level course. Small world of environmental geography! Foster's book was published in 1999, just as I was beginning to teach a course I would later rename Land Protection. At the time, he was the director of Harvard Forest, which my students and I were fortunate enough to visit several times with John O'Keefe, a forest ecologist who continued to host our visits for a number of years after his retirement. The combination of Foster's book and O'Keefe's many walks in the woods -- combined with a few sessions with more recent staff -- have allowed me to lead many student visits there in recent years. 

As I read the article, I saw quite a few references to Harvard Forest before seeing the mention of David Foster, who is not mentioned as the director, but rather by his affiliation with an initiative known as Wildlands, Woodlands, Farmlands, and Communities (again: very geographic!).

The article begins with someone who currently works at Harvard Forest. Erik Danielson is a self-taught dendrochronologist whose hobby is finding really big, really old trees. In the process, he has found patches of old-growth forest that have completely escaped the notice of other forestry experts. The article suggests, in fact, that Harvard Forest has purchased such a patch, about 30 miles north of its main properties. 

The article is a nice introduction to a central theme of my course and Foster's writing, which is that the reforesting of North America in general and New England in particular has continued since Thoreau's time but obscures the fact that almost all of the forests we see today are on land that was cleared for agriculture. Langlois goes a bit further, mentioning that much of what we see has been cleared again after its second growth. And maybe even again after that! 

She then reports on some of the scholarship around those old-growth patches that do remain, and some disagreements over exactly how they should be managed -- or perhaps benignly neglected. A familiar concept that she mentions is the effort to develop corridors of protected forests to maximize the resilience benefits of the genetic diversity contained in these relict patches. 

She also mentions -- though not by name -- the importance of buffer zones around the old-growth areas. I have thought -- and taught -- about buffers as a way to protect the integrity of key habitats. This is what the Massachusetts Biomap program calls Critical Natural Landscape. This article suggests a subtly different use of buffer zones. Second- and third-growth forests that surround old-growth forests can not only protect those rare patches: they can also provide a matrix into which they can expand. This cannot be true in a literal sense -- we cannot have new growth of old trees. But some ecologists are arguing that if left alone and surrounded by protected land, an expanded area could exhibit the essential characteristics of old-growth. 

Please read the entire article -- especially if you are in my Land Protection course -- for more insights about the spatial dimensions of forest ecology and forest protection.

Lagniappe: Coffee Connection

I plan to follow up with some of the Harvard Forest experts Langlois mentions, because there may be a benefit for coffee growers. My next sabbatical will be devoted to coffee on the island of Fogo in Cabo Verde. During my preliminary visit in 2024, I learned that a large proportion of the islands small coffee crop is harvested from trees that are over 100 years old. It is, of course, impossible to plant new 100-year old trees. But perhaps some lesson from Harvard Forest will provide benefits from those who work with those century trees.