A few weeks ago, after construction detours in Portland, Oregon sent me down a seemingly endless series of wrong turns, I stumbled across something I never thought I’d see in person: a monkey puzzle tree.
These bizarre, prehistoric-looking pine trees — Araucaria Araucana, also known as the pewen, piñonero, or monkey tail tree — have fascinated me ever since I first wrote about them in 2016. They’re massive trees, with sharp, scaly leaves that grow in a spiral pattern that looks more like an assemblage of succulent “hens and chicks” plants than your typical conifer.
Monkey puzzle trees are, surprisingly, fairly common in the Portland area, although they’ve eluded my sight until now. It turns out they’ve been here for 120 years, ever since the Chilean delegation to the 1905 Lewis and Clark Centennial Exposition gave seedlings to many attendees. Today the Portland government tracks a few of the city’s biggest monkey puzzle trees, a Google map tells you where to find the rest, and Oregon State University lists them as one of the region’s notable ornamental plants. There’s even a monkey puzzle tree farm about 100 miles south.
But to really understand monkey puzzle trees, you need to travel much further south — to their native South America.
I won’t be making it that far anytime soon, but here are 10 important facts I’ve gathered about these amazing trees over the past few years:
They’re big — and ancient. Monkey puzzles can grow to an amazing 130 feet in height and live for more than 1,200 years. The species has been around for millennia — their ancestors called the dinosaurs neighbors — and biologists consider them “living fossils.”
But they live in a very small habitat: The only grow naturally in a restricted range of about 150 square miles within the Andes in Chile and Argentina, where they’re adapted to cool, rainy weather (that explains why they do well in Portland).
Despite their Western name, no monkeys live near them. Their common moniker reportedly came about after a European commented that “it would puzzle a monkey to climb this tree,” due to their sharp branches and spikey leaves.
They’re endangered. As I wrote in 2016, “Logging for the trees’ famously hard wood took a toll during the 20th Century, and in this century fires have taken down huge swaths of the trees that remained. Non-native trees and agriculture have also carved up the surrounding habitat.”
But these trees face many other challenges, which we’ll get to in a moment.
Their seeds are important to both people and animals. The trees produce cones up to 7 or 8 inches wide, each of which can contain hundreds of tasty, nutritious seeds. The Mapuche (also known as the Araucanians, from which the trees’ scientific name is derived) depend on these seeds, particularly during the autumn months when other foods are scarce, according to an article from the Brooklyn Botanical Garden.
Animals partake of the seeds, as well. And as I wrote in 2016, “Austral parakeets (Enicognathus ferrugineus) and four species of native mice relied on the seeds of monkey puzzle trees for good portions of their diets.”
The trees, in turn, depend on native animals: As we see with many other plants, seed-eating animals helped disperse the seeds away from their parents, pooping out partially digested seeds that often benefit from that process and become more likely to sprout — especially if they’ve moved away from the roots and shade of their massive progenitors.
But colonists brought other animals: Colonialism was not good to the monkey puzzle tree. Settlers cleared the land for agriculture and imported many familiar species from home. From my 2016 article:
According to a paper published in Global Ecology and Conservation…European settlers brought with them a wide range of new livestock species, inducing cattle, goats, horses, sheep, and pigs. They also imported animals they wanted to hunt: wild boars (Sus scrofa), European hares (Lepus europaeus), European rabbits (Oryctolagus cuniculus), and red deer (Cervus elaphus). Many of those imports have now become out-of-control invasive species.
And all nine of these introduced species love monkey puzzle tree seeds.
To study the effect of these extra mouths, a team of Spanish and Argentinian researchers visited 516 female monkey puzzle trees throughout their range. They found that at least 90% of them were visited by one or more hungry exotic species. The researchers could tell which species ate the seeds by the way they opened or nibbled on the seed coats, or by finding partially digested seeds in feces.
The non-native species didn’t leave much behind. According to the paper, the majority of studied trees had fewer than 10 uneaten seeds on the ground around them. That’s a pretty low number when you consider that a single cone can contain 100 to 200 seeds, and each tree could produce hundreds of cones.
The cumulative effect, the authors wrote, is two-fold. For one thing, there are fewer seeds sitting on the ground year-round for native animals to eat. This interruption in their food cycle could cause their populations to decline.
For another, this leaves fewer seeds to end up in the ground. The authors reported that when trees were visited by 2-4 exotic species, they observed a resulting drastic reduction in young monkey puzzle tree seedlings. Those seedlings completely disappeared when the trees were visited by five or more exotic species.
This lack of recruitment, quite obviously, could affect the long-term survival rates of this living fossil.
Now new threats have emerged: Climate change, drought and fires have all taken a toll on the trees. On top of that, a rapidly spreading fungus called Pewenomyces kutranfy (named after the trees) turned up around 2015, causing wound-like cankers that ooze sap, killing approximately 2% of infected trees. We don’t yet know if this fungus came from somewhere else or if changing conditions allowed it to grow out of control.
And efforts to protect the trees may have created another problem. The Indigenous Pewenche people, among others, rely on the seeds of these trees as a staple of their diet. According to a paper published earlier this year, attempts to classify the trees as endangered caused confusion and resentment because they felt it would restrict their use of the seeds — an understandable perception, as conservation efforts have an unfortunate history of excluding Indigenous peoples.
Some of these species could bounce back: As the authors of the 2016 study noted, properly managing the introduced species (i.e., exterminating them) could help the monkey puzzle trees. They’re a long-lived species, after all, and the older a tree becomes the more seeds it produces. If mature trees survive, the species probably will, too.
The parakeet and the native mice, meanwhile, also feed upon a variety of other vegetation that live around the monkey puzzle trees, so there’s a chance they can adapt. But to my previous point, do we know that yet? It’s all uncertain.
We need to know more: Despite the emerging threats, science still has a long way to go to understand and preserve the monkey puzzle tree. The IUCN Red List entry for the species hasn’t been updated since its last assessment in 2011, and relatively few additional papers on the trees have been published in the past few years.
Meanwhile climate change, fires, and now fungi present force multipliers to threats that have been growing for centuries.
Monkey puzzle trees may hold on in cultivation in Portland and other cool-weather places around the world, but if we lose them in the wild in the Andes, the people and wildlife of the region will lose something that’s been a part of their lives for tens of thousands of years.
That’s not a puzzle: It’s a problem that needs to be addressed.
Previously in The Revelator:
Blood Is Life — The Amazing Dragon’s Blood Tree
