Matt Katz: You're listening to The Takeaway. I'm Matt Katz, in for Melissa Harris-Perry. I know it's wintertime and you might be tuning in while you're wrapped in a scarf or holding a hot cup of coffee for warmth, but it won't be long until we're comfortably outdoors again. We'll be looking for relief from climbing temperatures then wherever we can find it. I love a summer hike in the wood where the shade is plentiful and the temps are just a bit lower, and without even leaving the city I'm lucky to have parks near me with plenty of trees for that summer shade as the temperatures become more extreme, thanks to climate change.

It turns out that there's more to it than luck in terms of whether you're near trees or not, because urban planners have been disproportionately planting trees in specific areas for decades, according to the nonprofit American Forests. By planting more trees in one area and fewer in another, we're actually disadvantaging communities. Trees just don't shade us from the heat.

The Forest Service of the US Department of Agriculture indicates that trees reduce air pollution, improve our health, provide homes for wildlife, and increase the value of our homes. When we call attention to the disproportionate number of trees in certain areas of the country, we're talking about the necessity of tree equity, the ability for everyone to experience the benefit of trees regardless of who you are or where you live. Melissa Harris-Perry spoke with Vivek Shandas, Professor of Climate Adaptation at Portland State University.

Vivek Shandas: Tree equity, we've heard the term equity in so many different contexts. When we put trees and equity together, we're not talking about the trees per se, we're talking about the people that benefit from trees. The idea that trees are actually distributed in a particular pattern that we've been able to understand over the last couple of decades, that's really where a lot of this idea of tree equity comes from. The fact that trees are highly clustered in specific neighborhoods and cities, trees are not found in other parts of cities. That really is what we're talking about is how that distribution of trees occurred in the first place and what we might do to give people a bit more of the benefits that trees provide.

Melissa Harris-Perry: Let's walk through each piece of that. First, is this exclusively or primarily an urban problem, you said, how they're distributed in cities? Is this not a problem in suburbs or in more rural communities?

Vivek Shandas: No, it's a problem across the country in many respects. We've seen trees really get hit real hard by various heat waves, we've seen trees get scorched, we've seen fires really burn through large tracks of forests. Those are all things that happen outside of cities. The question of whether we're able to replant those trees, get those trees back, and providing the carbon sequestration, the cooling effects, all of the climate regulation that trees provide, is an essential part of being able to really balance out this planetary system. It is something that goes well beyond the boundaries of a city into suburbs, into the rural areas, into agricultural areas as well.

Melissa Harris-Perry: Maybe this is almost silly or too basic, but I think we sometimes need to be reminded, what exactly are the benefits of trees to people?

Vivek Shandas: I come from a school of thought that really focuses on the fact that humans and trees have coevolved together. We are part of a landscape that really depends on the oxygen that trees provide. Trees take in a lot of the carbon dioxide that we breathe out. Just by each breath we take, we have a symbiotic and mutually beneficial relationship with our leafy friends. Part of what that leads to is how does that link of oxygen and carbon dioxide lead to other benefits that humans have?

It really comes down to a whole decade-plus of studies that have really focused in on the fact that we have physiological benefits. That's respiratory health from the clean air that tree provide, cardiovascular benefits as a result of that. We have shade that trees provide as well as transpiration, which cools the environment. We have a lot of mental health benefits that trees provide as well. Communities that are in hospital rooms, for example, that have views of trees are actually healing much faster than those who don't.

These clinical studies have been conducted not only in laboratory settings but also in settings out in the field, and they've been corroborated for, again, many decades. This is something that we are starting to really understand, that we depend on trees and they provide us these valuable, what we call, ecosystem services. That's how nature benefits us throughout our day, throughout the year, and throughout our life. That's really something that we've got a really good handle on, and there's volumes of ink that have been spilled on describing the myriad ways that trees are benefiting humans.

Melissa Harris-Perry: Talk to me, given that notion of where trees are, the other piece of what you began with was this idea that they are in our built environment, whether urban or otherwise, they are not equitably distributed. Where are trees and how did they get there?

Vivek Shandas: I entered the tree conversation through understanding the distribution of where are the hottest areas in cities, where are the coolest areas in cities, where are the most polluted air pollution hotspots in cities, and where are they not. What I couldn't help but notice is this real interesting pattern of where there were more trees, it was on average 15, sometimes 20 degrees cooler in that neighborhood. That is what really I started scratching my head and asked my colleagues about, why am I seeing this pattern over and over?

It's really interesting that lower-income communities, communities of color, those areas that have been disinvested in over decades don't seem to have that cooler temperatures. It was very obvious when you looked at those neighborhoods that trees were conspicuously missing. When we started to dig into this a bit more, we started noticing that there were these patterns of specific policies that had played out over many decades that go back almost 80 to 100 years ago, that would segregate communities based on color of their skin, based on income, based on immigrant status.

Those communities would be in some neighborhoods back in the '30s, '40s, '50s, and '60s, and there were federal policies such as, for example, often known as redlining policies, that would codify the segregation in cities around the country. What we noticed was this pattern, those areas that were redlined, meaning they were segregated, those had far fewer trees and they were far hotter than their non-redlined counterparts. We were able to tie arguably one of the first studies to tie this relationship between what was happening almost 100 years ago to what we're experiencing in terms of temperatures today and in terms of the distribution of trees today.

Melissa Harris-Perry: I personally think that's absolutely fascinating. There's this social scientific practice of calling areas without things food deserts or information deserts. To find that there's actually this lack of tree canopy and to be able to map it onto those same inequities, it does suddenly make tree equity make sense as the phrase, even though when you very first see it, it seems as though you're talking about the equitable treatment of an oak tree versus a maple tree.

Vivek Shandas: That's exactly right. If the federal policies from the past are really contributing and have contributed to the distribution of trees, couldn't one simply argue that we need federal policies to write some of those wrongs? That's really what justice and equity looks like today in terms of questions about Build Back Better and the tree equity agenda that's embedded in that. Couldn't we argue that that is one of the ways in which the federal government can really move in a very promising direction to, again, write those wrongs that were done in the past?

Melissa Harris-Perry: How does Build Back Better address tree equity?

Vivek Shandas: Part of the challenge that many municipal governments face in terms of addressing this distribution of trees is that for decades we have paved out areas of cities with big-box stores, with industrial facilities, with large freeway projects and highway projects that went in the 1950s and '60s. Those large, land-hungry projects went into areas that were by design disinvested over time, and the land rents were intentionally suppressed. When you have that lower-cost land, the cost-benefit analysis that the local planners would pursue would say, "Hey, these are the areas to put the freeways, the big-box stores, the industrial facilities," and those are often adjacent to these redlined neighborhoods.

What we end up seeing in local municipal urban forestry agendas is an attempt to try to bring trees back into areas that would otherwise not be able to see trees. Tearing up a pavement or asphalt is not only a politically challenging agenda item, it's also very labor-intensive, cost-intensive. Where a lot of municipal governments are really caught flatfooted is, how do we fund urban forestry? How do we actually move trees into places where we can actually see communities that have been historically marginalized benefit from some of this green infrastructure, as it's often called now?

The federal Build Back Better policies could put some essential resources into local municipalities to start really moving the needle on getting trees more equitably distributed in neighborhoods that have historically not seen a lot of this greenery. Those federal resources are at a critical time where we're seeing heatwaves, where we're seeing flooding, where we're seeing air pollution at very high levels and really disproportionately affecting lower-income and communities of color, marginalized communities in the past. This is an essential step for us to really think about how do we support folks at the local level in doing the right thing.

Melissa Harris-Perry: We so enjoy and appreciate you taking time to talk with us. Vivek Shandas, Professor of Climate Adaptation at Portland State University.

Vivek Shandas: Thanks, Melissa. It was great to be here.

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