Planting trees has become a popular response to climate change. They absorb carbon dioxide from the atmosphere as they grow. Their canopies provide cooling shade in cities. And their root systems can prevent stormwater runoff and help stabilize steep slopes.
But how effective are tree planting efforts, really? A new book – Treekeepers: The Race for a Forested Future by Montana-based science writer Lauren Oakes – delves deep into that question, as well as the role of forests in addressing climate change. Oakes joined KNKX environment reporter Bellamy Pailthorp in Seattle’s largest contiguous forest, the West Duwamish Greenbelt, to learn more.
Click “Listen” above to hear their conversation, or find the transcript below.
Transcript
Note: This transcript is provided for reference only and may contain typos. Please confirm accuracy before quoting.
KNKX Environment reporter Bellamy Pailthorp: Lauren, welcome to Seattle. We're here standing in the city's largest contiguous forest in the West Duwamish green belt. It stretches some 550 acres. It's on the eastern flank of West Seattle, right next to the Duwamish industrial area. Why is a place like this and its enormous size important?
Author Lauren Oakes: First of all, it feels like a treat to spend more time here and just pause. I hear birds singing in the background. There's a diversity of trees and plant life here. And after driving across, you know, the bridge and seeing busy ships and the pollution, I am thinking about the many benefits that come from a place like this.
Trees and plant life here are helpful in mitigating some of that air pollution. They help cool the area through evapotranspiration. And of course, if this area extends over a larger landscape, we get more of that effect. They attract the other wildlife that we're hearing and that we see, and they provide enormous opportunity for community members here to experience the many benefits that come from just spending time in nature.
Pailthorp: You walk into a forest and you - you feel those benefits kind of innately. You walk in and it's like, ‘aaah….’ And there's actually people studying what that is and why that happens?
Oakes: I came to Seattle, I was researching my new book Treekeepers, and I spent some time at the University of Washington. There are a number of researchers there who are exploring these linkages between mental health and how your brain functions and the time that people spend in forests or in surrounding green spaces.
Greg Bratman is one of those researchers. One of his earliest studies when he was at Stanford was looking at, if someone took a 20-minute walk through an urban setting, versus a 20-minute walk through something like this, through this place, what were the effects on the brain? And they really saw decreased neural activity in parts that of the mind that are attributed to producing more anxiety. So, there really is a coming effect that comes, and I think Western science is starting to look more at and is looking more at what people have known for millennia, living in and with nature in a more balanced relationship, if you will.
Pailthorp: Right. There's the forest bathing movement that comes, I believe, from Asian cultures, right?
Oakes: Yeah. And actually, his research group has also been looking at this from a Western science perspective too, taking people into old growth forests, they actually regulate the terpenes that those people breathe through what kind of looks like an air respirator. So you're breathing terpenes. Terpenes, these are compounds released by trees that people also think, the theory is that they're also what's affecting our neural activity. So there's some interesting science trying to unpack those linkages as well.
Pailthorp: And your new book is called Treekeepers: the Race for a Forested Future. When did this trend of you know the popularity of tree planting start?
Oakes: In 2019, there was a study that came out in Science, very esteemed journal. They were essentially looking at how many more trees could the planet support, and what could they sequester, in terms of their carbon sequestration?
So at the dawn of human civilization, some studies have shown that we have about six that we had about 6 million trees. Now we're down to about 3 million...And then the study was saying, Okay, well, we could plant, there's room for another million, when you take into consideration all the other land use out there.
What got a lot of attention was a line saying that it's essentially, you know, the easiest mitigation strategy at our hands and available. So that's kind of when the movement took off...
I wrote another book called In Search of the Canary Tree, which is a lot about loss, and how do you recover from loss, and how do we remain hopeful, and how do we take action in this warming world? And in finishing that book, I was starting to look at countries and places that had been experiencing forest gain. So, these are countries like China, Bhutan, Costa Rica. And I was thinking this hopeful notion of, could we recreate forests? And if so, what are we recreating? Are they actually what they were?
Pailthorp: To your point, we're standing next to a jumble of different kinds of trees, and I wouldn't call most of them majestic.
Oakes: Yeah, yeah. There's cottonwoods, there's alders here. I saw some cedar when I was coming in. There's a diversity here, but together, I think they create their own ecosystem. And it may not have been what was here. I think this is a secondary, or maybe even a third growth forest. So it's, it's likely not a replicate of what was here hundreds of years ago, but it is a forest and another form of forest today.
Pailthorp: Seattle recently updated its tree protection ordinance. The goal was to balance the need for trees with the need for more housing. Critics, though, say it's no longer really protecting trees and that it favors developers' needs. And as I've followed this debate, it seems to me like tree protection in cities is a huge challenge, like, maybe trees don't really belong inside cities. Should we just go dense and have the urban zones without trees and put the trees on the outskirts?
Oakes: One of the things that really struck me when I was in Tacoma was learning that a lot of cities will get money, will have money to plant. And then who cares for the tree and who keeps it becomes the landowner adjacent to that, or the person renting there. And one of the things that stuck out to me from an interview was someone saying, like, what if our trees were like street lights, like we get funding to maintain them. If something goes wrong with the streetlight, like someone's going to go out there and fix that. In our dream world we would have trees in our cities that were like street lights.
And I love that, because it also highlights the critical role they play. Like street lights offer safety, they are part of the community. There's so many other benefits they provide that are critical, and I feel the same way about trees. So no, I don't want to see our cities just becoming increasingly dense and then nature being this other thing we go to, or maybe we can't go to because we don't have access, which is a whole other issue. But I think our sustainability moving forward will be dependent on the extent to which we learn to integrate nature and nature stewardship better into our daily lives, in any part of the world.
Pailthorp: Science writer and conservation scientist Lauren Oakes, thank you so much.
Oakes: Thank you for having me.
