The Problem of Tree Inequity: Redlining and its Contribution to Tree Inequity in Low Income Neighborhoods

Audience: The topic of this paper is tree inequity in low income neighborhoods. The intended audience of this paper would be environmentalists, forestry program or tree maintenance employees and volunteers, and urban planners including city sustainability or resilience coordinators. Their work generally entails working toward improving or conserving the environment. The intended audience is also local government officeholders and politicians like governors or state representatives. They may have some control over legislative changes concerning the environment or funding for environmental programs. Environmentalists, forestry programs and urban planners may be generally receptive to the argument that redlining has contributed to underprivileged communities lack of tree canopy as some forestry programs work towards ending tree inequity and they would be knowledgeable on this subject. The intended audience also understands that improving the city physically will not only benefit local communities but it will also make it more attractive and visually aesthetic to tourists among many others. Overall, these audiences should be aware of this issue as it affects people’s quality of life and they should take action like implementing policies and increasing funding in order to improve tree disparity and provide communities with the necessary resources. 

The Problem of Tree Inequity

Redlining and its Contribution to Tree Inequity in Low Income Neighborhoods

Have you noticed how some neighborhoods have fewer trees than others? Trees make for healthier people, ecosystems, and economies, but not everyone has access to them. In fact, disadvantaged communities across the United States have long suffered from the uneven distribution of street trees. Lower income communities face effects such as higher air pollution, higher temperatures, and – in part as a result of these two – serious health risks to human health. As a result, people of low socio-economic status are greatly impacted by tree disparity as the uneven distribution of trees primarily impacts lower income neighborhoods and deprives them of the benefits trees provide. One study found that “low-income blocks have 15.2% less tree cover” (McDonald et al.). Poorer communities often face the worst effects of gentrification as wealthier neighborhoods continue to become more environmentally friendly while poorer neighborhoods become less environmentally appealing. It is essential that environmentalists, local governments, and urban planners become more aware of this disparity to prevent it from worsening. A primary cause for this disparity is redlining. Redlining “was a racially discriminatory housing policy established by the federal government’s Home Owners’ Loan Corporation (HOLC) during the 1930s” (Locke et al.). It limited access to homeownership and wealth creation among racial minorities (Locke et al.). Neighborhoods were color coded in order of perceived risk of investment. Areas with lower grades such as a “D” grade were considered hazardous and consisted of racial and ethnic minorities (Locke et al.). Before this and other remedies can be attempted, communities and governments alike must first recognize both the existence of tree inequity and the lasting damage it inflicts on communities least capable of reversing it. 

In this paper, I examine how people of low income are primarily affected by the uneven distribution of trees and why action should be taken to fix this problem. Throughout this paper, my focus will be on the discriminatory federal policy of redlining and its long-term effects. First, I provide background on tree equity. I examine how redlining has contributed to tree inequity, preventing people from taking part in the benefits trees provide. I then describe how tree inequity affects people of low income through an increase of air pollution and temperature and how these increase health risks. Finally, showing redlining’s persistent effects even now, I look into what action should be taken to fight tree inequity due to a lack of trees affecting people’s quality of life and illustrate how we can work together to make sure people do want trees.

Tree equity means that every neighborhood has an equal distribution of trees so all people are able to have access to trees, therefore experiencing the benefits trees provide. In contrast, tree inequity refers to the disproportionate planting of trees. To calculate tree inequity, American Forests, a national nonprofit conservation organization focused on creating healthy forests, developed the Tree Equity Score (TES) and the Tree Equity Score Analyzer (TESA) to calculate how tree canopies and surface temperature align with income, employment, race, age and health factors in the U.S. Higher scores indicate better tree equity compared to low scores which indicate an uneven distribution or lack of trees in the area. Lower scores are seen in formerly redlined and lower-income neighborhoods as they experience much less tree cover compared to wealthier neighborhoods, who have more trees (American Forests).

Trees are important because of the many benefits they provide. According to an analysis on the benefits and limits of urban tree planting for environmental and human health, Pataki et found that “trees have localized effects on climate, thermal comfort, human health, and habitat for other species that may be impactful at the site scale” (6). A climate benefit that trees provide is the improvement of air quality which occurs when oxygen is produced through photosynthesis and when pollution such as particulate matter and gaseous air pollutants, like sulfur dioxide, is removed through tree’s leaf stomata (Nowak et al.). Another climate benefit trees provide is lower temperatures as “tree cover cools the air primarily by shading surfaces such as concrete and asphalt, thus preventing heat storage and reducing the urban heat island effect” (McDonald et al. 2). Trees also provide mental, physical and social health benefits. Leahy and Serkez stress the importance of having access to trees in their New York Times article, “Since When Have Trees Existed Only for Rich Americans?” by stating that “being in the presence of trees has also been found to improve youth educational performance, mental health, physical health and social connections” (Leahy and Serkez). 

Although trees provide many benefits, lower-income neighborhoods are not able to take part in these benefits as they experience low access to trees. It was found that low income neighborhoods and minority communities experience tree inequity as they often have less tree cover compared to wealthier areas (McDonald et al. 2). Gerrish and Watkins conducted a meta-analysis, or a study that statistically assesses the results of previous studies, and found evidence of income-based inequity in urban forest cover. Chuang et al. corroborates this correlation as they found evidence in their statistical analysis that relatively stable wealthy neighborhoods had more tree canopy, indicating that neighborhoods of other, specifically lower, socioeconomic status experienced lower tree coverage (Chuang et al. 371). As a result, lower income neighborhoods are deprived of the many benefits trees provide. Some of the benefits trees provide include better health outcomes and cognitive abilities (as exposure to greenspaces may help brain development, memory and attention span) as well as a better ability to cope with stress (due to greenery promoting relaxation and lowering the sympathetic nervous system’s activity which is related to stress) (Flocks et al. 126; Park et al. 21-24). There have also been economic benefits because of tree cover such as a reduction in energy use, due to less reliance on air conditioning thanks to the shade trees, and an increase in property values, due to the beautification of the property (Flocks et al. 127).  By not being able to partake in these benefits, low-income neighborhoods are done a disservice and their quality of life is impacted negatively.

The limited access to trees found in low-income areas may be primarily attributed to redlining, a discriminatory housing policy, as it seems to have played a role in the distribution of trees. Due to Americans struggling to pay mortgages in the wake of the Great Depression, agencies like the Home Owners Loan Corporation (HOLC) (1933) were established. The HOLC created guidelines based on housing market conditions, economic characteristics, and neighborhood demographics to appraise residential property values (Woodard). Maps were drawn up to represent cities across the U.S. Neighborhoods were color coded to reflect a rank in perceived risk of investment. The colors in neighborhood appraisal maps appeared as  “A” (green), “B” (blue), “C” (yellow), and “D” (red)” (Locke et al.). Areas graded “A” and “B” were considered safe for banks to invest in as they were “areas with predominantly U.S.-born, white populations, and newer housing stock”. Areas graded “C”  had “somewhat older structures and/or a presence of foreign-born residents'''. Areas graded “D” were considered “hazardous” and given the lowest grade. These areas had a significant number “of racial and ethnic minorities, foreign-born residents, families on relief, and having older housing” (Locke et al.). Thus the practice of redlining was conceived, due to banks, lenders and investors denying certain areas (usually those coded red) financial services such as loans, mortgages, and insurance among other services based on race and ethnicity (Woodard). Because these areas consisting of majority-minority communities were not considered high investment areas, they were and continue to be more likely to have their natural areas, especially tree canopies, disrupted. Many redlined neighborhoods had their environments disrupted because of the road and highway infrastructure construction as well as the construction of large building complexes in part, due to the inexpensive land and “current population of largely lower income and communities of color “(Hoffman et al.) This led to “increased impervious land cover and decreased tree canopy coverage with worsening HOLC grade” (Hoffman). Therefore, it can be said that due to redlining’s impacts, formerly redlined areas were found to have fewer trees (Plumer et al.). Locke et al. also found how formerly redlined areas experience lower tree cover by analyzing 37 metropolitan areas and finding how formerly graded D areas “have on average ~23% tree canopy cover today” compared to “areas formerly graded A, characterized by U.S.-born white populations living in newer housing stock, had nearly twice as much tree canopy (~43%)” (Locke et al.). This shows how areas that were redlined have a significantly lower amount of trees compared to non-redlined areas.

One significant consequence of low street tree coverage that lower-income communities face is increased air pollution. In a systematic review done by Hajat et al., a consistent finding was found in which lower socio-economic status (SES) individuals and communities were exposed to higher concentrations of air pollutants (4). One of the many ways that urban trees affect air quality is through pollution removal. Trees remove air pollutants such as carbon dioxide (CO₂ ) through the leaf’s stomata and store CO₂  in their fibers. While pollution removal rates differ among cities according to the amount of air pollution and other variables, “pollution removal by urban trees in the United States has been estimated at 711,000 tonnes (t) per year” (Nowak et al. 119).  However, this pollution removal can only occur if there are trees. This indicates in part that due to a lack of tree cover, lower income blocks experience more pollution  because they don’t have adequate tree cover that leads to more pollution removal. The lack of sufficient tree coverage also shows that since lower income neighborhoods have less tree coverage, they are not able to experience the benefits more cover provides and instead are faced with more pollution which leads to an increase in the possibility of health risks. These health risks may include respiratory diseases like asthma and cardiovascular diseases. According to Nardone et al. in “Associations between historical residential redlining and current age-adjusted rates of emergency department visits due to asthma across eight cities in California: an ecological study”, “redlining policies...denied wealth generating opportunities in communities of colour and undermined the physical environments of neighbourhoods” (28). These environments were undermined by  “local zoning officials [working] with businesses to place polluting operations such as industrial plants, major roadways and shipping ports in and around neighborhoods that the federal government marginalized” causing their physical environment to be disrupted (Fears). This led to lower tree coverage in redlined areas and more pollution. As a result, “Historically redlined census tracts have significantly higher rates of emergency department visits due to asthma, suggesting that this discriminatory practice might be contributing to racial and ethnic asthma health disparities” (Nardone et al. 24). Due to formally redlined areas lacking greenspaces, the levels of air pollution rise show how redlining has not only affected greenspaces but has also led to health disparities, which may be caused by increased exposure to air pollution. However, “reduced asthma hospitalization” was seen to occur in areas with high “tree density during periods with high ambient pollutant concentrations” (Wolf et al. 6). This shows the importance of trees as the presence of trees removes air pollution and decreases the risk of respiratory diseases, like asthma, and hospitalizations. This suggests that if lower-income blocks had more tree coverage, which can be achieved by more trees being planted in these areas, lower-income blocks would be able to experience more air pollution removal consequently improving health and allowing lower-income people to experience trees’ benefits. 

Another consequence of  low tree coverage is an increase in temperature. McDonald et al. stated that lower income blocks experience less tree cover which leads to higher temperatures as there aren’t trees to cool down the area or provide shade. Areas with places with more trees compared to areas with less trees may vary by 10 degrees (Leahy and Serkez). This is due to the heat island effect which occurs when “urbanized areas that experience higher temperatures than outlying areas” (EPA). This is more common in areas with limited greenery due to structures such as buildings, roads, and other infrastructure absorbing and re-emitting the sun’s heat more than greenery (EPA). In their New York Times article, “How Decades of Racist Housing Policy Left Neighborhoods Sweltering”, Plumer et al., shows how higher temperatures can be harmful to one’s health as they state that “even small differences in heat can be dangerous...every one degree increase in temperature can increase the risk of dying by 2.5 percent. Higher temperatures can strain the heart and make breathing more difficult, increasing hospitalization rates for cardiac arrest and respiratory diseases like asthma”. By not having sufficient tree cover to provide shade or cool down the area, lower income neighborhoods are faced with increased temperatures that negatively impacts their health. The article goes on to provide an example of an area with few trees that experiences hotter temperatures. This area is a formerly redlined neighborhood and still feels redlining’s effects today as it experiences low tree coverage. They describe the neighborhood of Gilpin in Richmond, VA which is covered with concrete, which traps heat and creates heat islands, and has few trees to provide shade. They go on to state that due to this, this neighborhood faces an increase in temperature that leads the people in the neighborhood to have “the highest rates of heat-related ambulance calls in the city.”  Due to redlining lasting effects, people are impacted by things like an increase in temperature, which poses health risks like heat stroke. The lack of trees low-income neighborhoods face poses a great disservice to their quality of life as it impacts their health in harmful ways and emphasizes the need for more trees in these areas. 

While redlining, a federal policy, has been outlawed (1968), its lasting effects are still felt to this day. Redlining does not only make formerly redlined areas experience more environmental hazards but it contributes to today’s racial wealth gap, where “white families today have nearly 10 times the net worth of black families and more than eight times that of Hispanic families, according to the Federal Reserve” (Jan). Discriminatory policies kept formerly redlined areas segregated and made it harder for residents to accumulate wealth for many reasons, one of those being undervalued homes (Garber). These policies have also contributed to communities susceptibility to gentrification, or changes in neighborhoods such as “economic change in a historically disinvested neighborhood —by means of real estate investment and new higher-income residents moving in – as well as demographic change – not only in terms of income level, but also in terms of changes in the education level or racial make-up of residents” (Urban Displacement). As a result of this economic change, many residents are displaced or pushed out of these neighborhoods because they cannot afford increased rent prices or property taxes (Jan). 

But combatting redlining is not so simple. The absence of trees has created historical damage over time. Plumer et al. in their New York Times article, “How Decades of Racist Housing Policy Left Neighborhoods Sweltering”, state that “Formerly redlined areas have less tree cover today than areas that weren’t redlined”.  These areas have more impervious surfaces leading to less soil for tree growth. They are also  already facing the consequences an absence of trees brings such environmental hazards, like extreme heat. Even though conscious efforts have been taken to reduce redlining, ecologically these areas are fighting against history.

This inequity cannot be solved by just planting trees. Planting more trees also comes with its own problems as “planting trees in neighborhoods can exacerbate gentrification. It can increase property values, making it hard for people to pay their rent or mortgage” (Grover). Instead, it is important to build strategic plans to ensure that all neighborhoods receive adequate tree coverage, no matter socio-economic status. 

To help mitigate the harmful effects of tree sparsity, not only do more trees have to be planted–they have to be planted in a way that directly combats tree inequities. According to the 2021 Tree Equity Score, 522 million trees need to be planted and grown across urbanized America. Jad Daley, president and chief executive officer of American Forests, stated that “Tree Equity Scores steers us in the right direction, and now it’s up to all of us to go beyond business as usual and take bold action” (Gammon). Since these scores indicate whether neighborhoods have enough trees to experience the full benefits of trees, government agencies, on all levels, should take Tree Equity scores into account when planting trees. They should call upon organizations like American Forests to ensure that tree equity is adhered to and areas with lower    TES are tackled first and gain sufficient tree cover to be able to receive trees’ benefits. A look into the work that American Forests has already accomplished in cities such as Los Angeles and Phoenix show how tree equity is a realizable goal. They have also created diverse partnerships in cities to develop comprehensive strategies that will result in a healthier, larger and better maintained tree canopy  (Gammon). For example, cities like Los Angeles have decided to invest in shade equity (Los Angeles mayor, Eric Garcetti, appointed a city forest officer to oversee the planting of 90,000 trees in areas lacking shade) and Phoenix, who has pledged tree equity by 2030 using American Forests’ impact model to reach this goal (Gammon).

To bring these strategies to life, funding is needed. Baltimore is another city attempting to fight tree disparity and urban heat. They are attempting to maintain and strategically plant more trees in low income neighborhoods among other things but are not on track to meet their goal of increasing the tree canopy to 40% by 2037  (Anderson and McMinn). This is in part due to a lack of funding. According to American Forests’ impact model, “existing levels of funding for urban forestry are inadequate” (Gammon). With more funding, these programs would be able to expand their workforce, providing people with more jobs, and the ability to plant more trees as well as provide better tree maintenance. Due to programs being limited, all levels of government (local, state, and federal) should provide funding to these programs in order to close the tree cover gap so all citizens receive trees’ benefits.

 Federal funding should especially be provided because federal problems require federal solutions.  For example, the U.S Federal Government stepped in to enact social justice and combat the harmful effects of discrimation by banning discriminatory housing practices in the 1950s, and ending racial segragtion with the Brown v. Board of Education decision in 1954. As this suggests, the federal government should also take action against tree inequity because redlining was a federal practice whose harmful effects continue to affect citizens and their quality of life. 

While the planting of new trees would provide people with many benefits, not everyone wants more trees planted. For instance, roughly 25% citizens of Detroit submitted "no-tree requests" between 2011 and 2014 alone (University of Vermont). Many citizens were wary of trees being planted because of previous negative experiences. The tree maintenance program in Detroit had undergone budget cuts, preventing them from fully carrying out their job thus resulting in “an estimated 20,000 dead or hazardous trees” in 2014 alone (University of Vermont). This led citizens to believe that more trees would require more work from them. A community member stated that, "Even though it's city property, we're gonna end up having to care for it and raking leaves and God knows whatever else we might have to do” (University of Vermont). Many community members shared this same sentiment. This skepticism about new plantings is a common occurrence in the United States as cities have done a poor job of maintaining existing trees in many neighborhoods leading to damages to houses and cars due to fallen trees. Despite concerns about additional trees being planted, social justice and environmental concerns should encourage and require this course of action (planting more trees) in order to fight against tree inequity.  

Opponents of tree equity initiatives often raise the concern that existing programs do not have the resources, the training, and the education to provide proper maintenance and to ensure both safety and equity with its initiatives. They are correct to hold these concerns. This is why local, state, and even federal funding must be granted to these programs. The benefits are too great and the harms to those without tree canopies are too severe. Due to things like budget cuts, programs do not have the resources to provide proper maintenance. Programs also face issues like being understaffed, which may be an effect of budget cuts, preventing them from having a large enough workforce to provide maintenance. Residents may also be limited by income constraints and renting tenure, preventing them from having control over their physical environment. This may result in residents relying on local or community forestry programs to provide maintenance, but if the program is not able to do that it may lead to negative views against trees on residents' part as the tree maintenance would fall on them and they may view tree maintenance as too much of a hassle or a burden. However, to fix this more federal funding can be provided to local or state programs in order to prevent budget cuts that may lead to negative situations, like the one Detroit citizens faced. Policymakers must also acknowledge how policies like redlining have affected the presence of trees. By providing more funding forestry programs will be able to provide better maintenance. 

The task ahead is not only difficult to achieve in terms of funding but also in terms of education. Forestry programs must also make better decisions and take residents' opinions into consideration to avoid mistrust. These planting programs should also try to select and plant trees that can survive the local urban environments. Better maintenance to the newly planted trees as well as pre-existing trees should be provided in order to effectively tackle the problem of tree inequity.  In order to achieve this, it’s crucial to employ scholars and researchers who have performed academic studies like arborists and managers who have led successful tree equity projects that consider the challenges of climate change. An example of this is seen in Rhode Island, as O’Rourke, the Rhode Island resilience officer, takes climate projections into consideration and looks to plant more Southern species (Brown). This strategy helps prevent tree loss, and helps the survival of trees would help close the tree disparity gap.

    Due to tree inequity, many citizens of color and citizens of low-income communities are deprived of the benefits trees provide. Tree inequity stems from redlining as redlining limits access to wealth creation and homeownership. Tree inequity is one of the many ways in which poor communities and communities that majorly consist of minorities are affected by redlining. Because of ongoing climate challenges, tree inequities could have just as devastating an impact on the poor and citizens of majority-minority communities due the consequences low tree coverage brings as redlining has with denying citizens financial services. Collaboration at all levels of government (local, state, and federal) is needed to tackle and erase the tree inequities that many neighborhoods face. All neighborhoods deserve the right to trees; it’s time the problem of tree inequity is addressed.

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