Episode 5: Is tree planting equitable?

Hey there!

“Environmental justice” was a relatively new term for me when I interviewed today’s guest, Shannon Lea Watkins.

Shannon is a post-doctoral fellow who studies (in, uh, layman’s terms) how trees influence people and how people influence trees, and she recently published a study that asked an uncomfortable but important question:

Is tree planting equitable? Do subsidized trees distributed by non-profits get planted evenly across the city, regardless of income or race?

Her findings explored two important components of environmental justice: access to natural resources and unequal exposure to environmental harms, AND access to the decision-making process. Shannon is finding that there is more to the story than just “trees are good.”

Talking with Shannon made me question some of my own assumptions and thinking, and left me with a lot to reflect on. I hope hearing our conversation does the same for you.

Listen to the episode by clicking the player above, or by going to iTunes, SoundCloud, or Google Play (and the full transcript is included below). We’d love to hear what you think about this episode and this topic — if you have something you want to share, please Tweet to @remarkableshow.

Thanks for listening.

Leda Marritz | Creative Director, DeepRoot


TRANSCRIPT: In tree planting equitable?

GUEST: Shannon Lea Watkins, postdoctoral fellow at University of California — San Francisco


When I think about environmental justice, I think about a few things. I think about access to natural resources and unequal exposure to environmental harms, but it’s also, I also think about access to the process. So this narrative of “Trees are good, and we will plant trees, and these communities will be better” I think does a disservice to those communities. It might be the case that trees are good and it will help that neighborhood. But in all of those decisions, engaging with the community and understanding THEIR needs and how we can contribute the expert knowledge of the non-profit and resources to helping neighborhoods achieve their goals.

One phrase that I have heard that concerns me is, something like “oh, if they only knew the benefits of trees.” You know, I don’t think that’s the story, I don’t think the story is… MOST of us don’t know the benefits of trees! We might think “Oh, those make me feel nice,” but we’re not actively thinking about that either.

So I think it’s not about knowing the benefits of trees. It’s about something else. And we’re working to figure out what that is.

My name is Shannon Lea Watkins; I’m a post-doctoral fellow at San Francisco State University.

I’m Leda Marritz, and this is Remarkable Objects, a podcast from DeepRoot about the intersection of nature and the urban environment.

Shannon and her research team — the Bloomington Urban Forestry Research Group, out of Indiana University – are working on a really interesting question. They want to know whether non-profit groups plant trees equitably. That is, are trees planted where they’re needed the most? And are they planted evenly across neighborhoods, regardless of the race or ethnic makeup of the residents?

To explore this question, they collaborated with four non-profits in four different U.S. cities. While their study tracks the spatial distribution of trees, it fits into a larger set of questions about human behavior, history, and the urban environment. What historical factors have driven inequity in tree distribution? How do tree planting decisions get made? What does it really mean to involve a community in shaping its urban forest?

Shannon and her co-authors found that as the African American population in a neighborhood increased by 1 percentage point, the probability that it had a tree planting decreased by as much as .25 percentage points. We had Shannon do some calculations to help us wrap our heads around what this really means. So, as an example, let’s compare two neighborhoods that are identical in all respects, except for the percentage of African American residents. One neighborhood is 25% African American, and the other is 75% African American. This study found that the neighborhood with the lower African American population would be about 64% more likely to have a tree planting than the one with the higher African American population. 

There is a vast body of research that demonstrates that trees have multiple, significant benefits for human health and wellbeing. Studies have also demonstrated that tree plantings by city governments are likelier to occur in low-canopy, low-income neighborhoods. But nonprofit programs, and race and ethnicity, are factors that haven’t been examined closely before.

What do we currently know about how household income and race and predict access to nature in urban areas?

The environmental justice hypothesis says that folks of lower income or neighborhoods of higher minority distribution, or higher minority concentration of residents, have less access to a variety of natural things like trees, parks, greenspace, and are more exposed to pollution. We have lots of examples where that’s the case.

The question about what we know on trend and what do we really know across the entire country is harder to answer. We have lots of studies where people have looked in one city and they say, “OK, here’s the distribution of canopy cover,” maybe they define it just where people live in residential areas. Maybe they look at only the trees along the streets.

So, we have evidence of many instances of inequity, but the story is more complex than to say that it’s is always the case in all cities.

Tell us the name of your study and what you looked at.

The short version of the title is, “Is planting equitable?” And that is the question. This paper spun out of a larger interdisciplinary research project that looked at the impact of people on trees and of trees on people, and we were interested in non-profit tree planting programs, and whether the choices that the non-profits and the neighborhoods made in planting and caring for those trees influenced how the trees did, and whether planting and caring for those trees as a neighborhood influenced the neighborhood in some way.

As we were working on that project, I realized that this would be quite an interesting case to look at the distribution of those trees. So are the trees, and the related benefits of those trees, going to places that could use trees, and could use trees that are subsidized by non-profits and city money? We wanted to know where the trees that the non-profits were planting were going.

Let me stop you for a moment and ask, what are some of the factors that might affect where trees get planted?

So you might have a program like a 311 program, where you can call in and request a tree. What happens if you have an opt-in program like that? Well you might have folks who know about the resource calling in, who have time to call in, and maybe you’re not actually planting trees in the places you want them to be planted.

Shannon and her team suggest in their paper that there were four factors that may have affected where trees got planted. Those factors were: (1) the physical suitability of the planting site, (2) funding sources, (3) neighborhood interest and capacity, and (4) the    mission of the non-profit.

Prior studies of city government programs had found that tree planting was more likely to happen where the urban canopy cover was already high, and in neighborhoods of higher income. And they didn’t look at race at all. While these are just a couple of studies in a couple of cities, the initial findings were problematic from the perspective of environmental justice.

You and your team added race and ethnicity to the mix in your study of non-profit planting programs, and found something different, or something deeper, than those earlier city studies.

So in these non-profit plantings, we looked at whether the trees were going in areas of higher canopy cover, whether they’re going in places of higher income, and whether they’re going in places with fewer minority residents.

We found, contrary to the city studies, that the non-profit trees are more likely to be planted in a neighborhood as canopy cover in that neighborhood is lower, which sounds like a good thing, right? We’re targeting places that could use canopy cover – we might be reducing differences in canopy cover across the city. We also find that the trees are more likely to go in neighborhoods as median household income is lower – which also suggests that trees are going to places where folks might not be able to afford trees without being subsidized by the non-profit or city funding. So those two things suggest really great things.

Now the other studies hadn’t, to my knowledge, looked at race and ethnicity alone – and so we also looked at that and we found that plantings are less likely to go in neighborhoods as the proportion of minority residents increases, which is potentially problematic, but we still don’t know the story behind why.

When we were talking before this interview, you mentioned that there are historical mechanisms that have led us to get the urban canopy distribution that we have today. What is a historical condition that would have affected today’s neighborhoods and driven them towards an unequal distribution of trees of the sort that you’re now studying?

We know that race and ethnicity play a historic role in where people live. We know that in the United States that there, that folks have been excluded from certain neighborhoods in policy and in social pressure. Right?

In the ‘50s, we have huge moves to suburban America, and far before that racially-based housing segregation. And all of that, that dictates where people move, you know, is related because trees are an intergenerational good.

We can see this more readily in a forest for example. If we think about the redwoods, the only reason we have them now is because10 years ago people protected the redwoods, and 20 years ago people protected the redwoods, and 30 years ago people protected the redwoods, right? So it’s intergenerational. In order for it to be maintained we need sort of continual efforts. And urban trees are the same. The lifespan of urban trees is shorter than the lifespan of trees in a forest. But they are, the trees that are in the ground now for the most part are evidence of what was happening, you know, 20, 50, 80 years ago.

And so, why are we not thinking about race and ethnicity?

Do you have any theories about why fewer trees were being planted in minority neighborhoods, at least at these non-profits you were working with for this study?

There could be any number of reasons. So there are a few steps at which this tree-planting process occurs.

The first step is having applications. We’ll use a really oversimplified dichotomy – perhaps minority neighborhoods are less likely to apply for the program at all. So it could happen at the application process.

It could happen at the selection process – perhaps there’s something about those neighborhoods, overt or covert, in the selection process that leads those minority neighborhoods not to be selected.

We don’t have data on all the applications the non-profit receives, so we can’t actually answer that question yet, but we could work with them to collect that data over a number of years and look at their selection process.

And I want to be careful; it’s not necessarily that the non-profit is looking at all the neighborhoods in a city and saying “oh, well let’s go plant…” – you know, we’re not sort of prescribing active choices PERHAPS, although if this is one of their goals we would suggest that they become active goals, right, in searching for neighborhoods that are interested that also are low canopy, low income, minority neighborhoods.

Could there be barriers at play on the community side of things as well?

There could be lots of barriers. Concerns about gentrification could be playing into it, different preferences, different experiences with trees. Perhaps if trees are not well maintained in those neighborhoods then, you know, residents aren’t interested in more trees. That’s one of the things to think about while planting trees, right: how do we serve the people that actually live there and aren’t creating change that would result in increased pressures on those residents.

We want to be supporting their neighborhood that is theirs, rather than just creating the physical conditions in a neighborhood that someone would enjoy, we want to speak to the people who live there and to protect those people.

So given that this could be occurring at a number of points in the process of getting trees planted, what are some ways to go about addressing the inequity in communities that do want trees?

Yeah so this goes back to at what stage does it happen.

If it happens at the pre-application process, you know, reaching out to neighborhoods and providing the resources and access to the non-profit in those neighborhoods might be the strategy, and then to support through an application process. So if an application requires some sort of plan at the neighborhood level, providing resources to help neighborhoods formulate those plans can help, you know, maybe increase the diversity of your applicants. So if it’s at that stage that would be one strategy.

If it’s at the neighborhood selection stage, if you look at a set of applications, maybe folks aren’t thinking about race when you’re making those decisions. But it could be influencing your decisions anyway. Are we eliminating neighborhoods in the application process – and again, this is just a question I don’t know the answer to – are you eliminating neighborhoods in the application process because of physical space when we could actually be doing something different?

So in Philadelphia, for example, trees are planted in pits in the sidewalk, so in order to plant a tree the pit has to be there, or you have to create the pit. So can we create pits, can we go put pits in places so that we increase the planting potential in that neighborhood? Something like that. Maybe it’s not a tree planting thing, maybe it’s a sidewalk question.

Talking across, from the non-profit to the city and back, is also important and something we found in our research. You know, making sure where you’re planting is going to be there five years from now! Does the city have any plans for tearing out that sidewalk? Do they have plans for widening the road? Do they have, you know, other plans? Or do you know that the trees you’re putting in are going to stay there.

So much of the challenge of trees is the longitudinal nature of their impact. So what I’m getting at, or trying to get at with this question, is whether we can make any educated predictions about neighborhoods 30, 40, 50 years from now, relative to equity, based on what you’re seeing?

If we look at the current drivers, and this is an area where I don’t think there is as much research – this paper is trying to contribute to that – the papers that look at city plantings are trying to contribute to that, right? What are the choices that we make now have, you know, how will those influence the urban forest in 20 or 50 years?

If we find that trees are going in low canopy-cover neighborhoods, that suggests that that we will see more homogenization of canopy cover. But, if we find that trees are going in whiter neighborhoods, maybe we’ll see greater inequity.  But, of course, people are also moving, and a city like San Francisco for example, is experiencing incredible gentrification and movement of people. So, will it be the case that the neighborhoods that are majority white now, or majority minority, remain the same? I really do not know.

Race and ethnicity are really important and also seem as though they could be really complicated to research. How do you incorporate principles of environmental justice in your work, despite academia being fairly un-diverse racially?

It’s a really good thing to think about our role as researchers, right? Learning about how to think through issues of equity is really quite important; making sure that we’re empowering rather than sort of speaking for is important. But yeah, I think working and working and working and continually striving to speak for the folks we purport to care about through listening to them.

It’s something I continually work on. I’m a white woman and I want to be contributing, and so it’s something I’m continually working on. And there are many scholars have been working on this for many years. The environmental justice movement isn’t just in academia. This is part of the civil rights movement. People and people of color have been working on this for many, many years. And so, I am also learning, I’ve committed myself to a lifetime of learning, and so I don’t want to speak too narrowly.

What’s coming next for this project? What can we look out for? 

For this research project, we’ve conducted interviews in many study neighborhoods that had these tree planting projects, and so right now we’re looking through those stories from the neighborhoods to see their experience with tree planting, why they started the project, whether the project benefitted that neighborhood.

Is there anything I didn’t ask you about that you’d want to make sure was included in a discussion about environmental justice?

A racist outcome or an act need not be malicious or intentional. We see inequity in canopy cover. And if we think about environmental injustice or environmental racism, that speaks to that problem. It need not come out explicitly, intentionally racist acts. But the result is still unequal and problematic.

I think a general statement about where cities are headed. We can see in San Francisco that things are changing very fast, and just to make sure that environmental justice in not just about outcomes, it’s about process. And access to the process. And influence in decision making, not just about the environment, but about cities and as cities change, who gets a say in what is happening.

Since we recorded this conversation, Shannon has switched positions. She is now a postdoctoral fellow at University of California, San Francisco. If you want to read more about her and her team’s work, including the paper we discussed in this episode, you can find links in the description for this show.

Remarkable Objects is produced and edited by me, Leda Marritz, with editorial assistance from Aylara Odekova. You can find us online at remarkableobjects.com, and on Twitter (@RemarkableShow). This podcast is a production of DeepRoot Green Infrastructure. DeepRoot provides landscape solutions and technical support services to promote mature tree growth and sustainable stormwater management in the built environment. Find out more at deeproot.com.

And if you like what we’re doing with Remarkable Objects, let us know by telling a friend, or giving us a rating or review in the iTunes store! It helps us reach more listeners, plus – it makes us feel good! Thanks.



“Broke for Free,” “Summer Spliffs” (Broke for Free)
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  1. I have never thought of this to even be a sitaution. But now that I think of it it sadly sounds about right. Great post. Thanks.

  2. Thanks for providing helpful information. This post contains many helpful information. Keep up it in future.

    Again Thanks

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