Growing equity from the ground up with municipal tree-planting

By treating trees as critical green infrastructure, U.S. cities are reducing urban heat island effects and revitalizing communities.

Feature image: The North Lawndale Tree Ambassador training in Chicago. Photo credit: Raed Mansour.

One of Phoenix Mayor Kate Gallego's earliest memories is of helping to plant a cottonwood tree at a park in her native Albuquerque when she was just three years old.

"I don't really remember anything else from being three, but the reason I remember that is because I went back to that tree every year," Gallego says. "I felt pride in helping plant it. If you plant a tree, you're quite likely to remember which one you planted and feel connected to your community."

Today, as mayor of one of America's hottest cities, Gallego is working to create similar community connections-and critical shade coverage-in Phoenix. In 2021, the LEED Platinum city of Phoenix became the first city in the U.S. to commit to achieving full tree equity, with a goal of ensuring that all neighborhoods across the city equally benefit from tree canopy coverage by 2030. In November 2024, the city adopted the Shade Phoenix master plan, backed by $60 million in public and private investments over five years that will result in 27,000 new trees and 550 new shade structures.

What's happening in Phoenix is part of a nationwide recognition that trees aren't just "nice to have" amenities or attractive neighborhood accents, but rather critical infrastructure that can yield benefits including better air quality, reduced stormwater runoff and-perhaps most critically-relief from the extreme heat that many cities are experiencing.

The Inflation Reduction Act of 2022 directed $50 million of funding to American Forests for tree planting. The nonprofit has already directed half of that funding to three dozen cities across the country, with the rest set to flow to community groups, including environmental justice and faith-based organizations.

"Trees are living infrastructure," says Benita Hussain, chief program officer for tree equity at American Forests. As the organization notes in a recent article: "On average, low-income communities have 38% less tree cover than wealthier ones, while communities with a majority of people of color have 26% less tree cover than majority-white neighborhoods."

"It's not just about shade," Hussain says. "When you're looking at communities that are 12 to 20 degrees hotter, it becomes a life-or-death issue."

Mayor Kate Gallego announces the city's new Shade Phoenix Plan at Solano Elementary School. Photo courtesy of the City of Phoenix.

More than a "photo op"

The importance of trees is recognized in a number of different ways by the LEED for Cities rating system, explains Hilari Varnadore, vice president for cities at USGBC. "We have a credit that addresses access to green spaces," Varnadore notes. "We've been addressing access in the rating since it was developed, particularly around the distribution of benefits and amenities-not just where trees are located, but also access to parks and libraries and good schools-and we've added a new option in our latest version for urban forest cover, where cities can demonstrate an improvement in forest cover or reduction in the urban heat map over 10 years."

To earn that option within the credit (in LEED for Cities v4.1), cities need to have an urban forest master plan in place.

Varnadore acknowledges that even she overlooked the importance of trees early in her career. "When I was right out of school, I was organizing tree plantings with community groups all the time and asking myself: 'Is this making an impact?'" she says. "But now, later in my career, I see that tree plantings may be one of the easiest ways to make an impact."

Jake Simon, southwest regional senior manager for urban forestry at American Forests, says these sorts of misconceptions are common, with natural solutions like trees not always taken as seriously as sophisticated green technologies. "Trees are often viewed as just a fun photo op," Simon says. "People think of them as something that's nice to have if there's money left over in the budget, but I do think, especially here in the southwest, cities are really starting to recognize that trees are critical infrastructure."

Beyond their environmental impact, Hussain notes, trees are also associated with higher property values, reduced crime rates and even improvements in human health outcomes. American Forests began focusing on tree equity in 2018, and the organization has developed a metric called the Tree Equity Score to help cities measure and track how the benefits of trees are distributed across neighborhoods.

The language of infrastructure, Hussain says, is essential for ensuring that public officials prioritize trees as they are making urban planning decisions. "If we don't treat this like infrastructure-if we don't bring public works and transportation departments to the table-then trees will always be left behind infrastructure like sewers and sidewalks and streetlights."

Hussain adds: "We're saying, let's include trees when we think about the built environment. Let's include trees when we think about housing. Let's think about trees alongside all of these other services."

Left: Jake Simon of American Forests gives an educational talk at an elementary school where he supports a Keep Phoenix Beautiful planting. Photo courtesy of Jake Simon. Right: Over 250 trees were planted at Cesar Chavez Park as part of Phoenix's first "cool corridor" to reduce heat and provide shade. Photo courtesy of the City of Phoenix.

An oasis in Phoenix

Many Phoenix residents don't need to be convinced of the benefits of trees. Simon says he'll often go out of his way to shop at a grocery store with a shaded parking lot during the summer, when asphalt temperatures can reach 170 degrees-literally almost hot enough to boil water. In the affluent, mostly white suburb of Paradise Valley, he says, temperatures are 10 to 15 degrees cooler than the average for the area. Meanwhile, in the town of Tolleson, which has higher levels of poverty, temperatures are 10 to 12 degrees hotter than average.

In 2023, Simon notes, heat-related deaths in Maricopa County alone (where Phoenix is located) eclipsed homicide numbers for the entire state, underscoring just how extreme weather has become in the region. "Look at the resources that go into preventing and investigating homicide, which obviously is a good thing," Simon says. "I think people are starting to realize that we can't air-condition our way out of this heat, and trees are by far the best solution when it comes to natural solutions to extreme heat management."

In addition to providing shade, Simon points out, trees alleviate urban heat islands through evapotranspiration, a process that cools the surrounding air by releasing water into the atmosphere.

Gallego herself frequently attends community tree-planting events, working alongside neighborhood groups, religious communities and schoolchildren to get trees in the ground. In 2019, for example, the city's Sikh community planted 550 trees-one for each year since the birth of Guru Narak, the founder of the religion. In 2023, the city held a planting event at a park to honor former mayor Terry Goddard, who told Gallego that he preferred trees to "another plaque."

"My favorite events are at schools," Gallego says. "It's very hands-on. They're making their own playground a more beautiful, cooler place. You get to teach kids about science. I think elementary school students, in particular, really find wonder in trees."

Gallego notes that trees also resonate with the city's grown-up residents, even those who aren't necessarily passionate about sustainability issues. "Residents love trees, and they are constantly asking for more," she says. "It's probably one of the top three things I get asked about. We had an election, and bond funding to reduce the impact of heat was among the most popular issues. That was not true of everything focused on sustainability. We know that trees create much cooler, more comfortable corridors. That's important to our community."

Eighty-five percent of Phoenix's tree investments will be focused on low- and middle-income communities.

Given Phoenix's climate, tree species must be selected carefully. (The cottonwood that Gallego planted in New Mexico as a child would quickly wither under the Arizona sun, which is more hospitable to species like palo verde trees, mesquites, and desert willows.) In addition, city workers must install irrigation infrastructure before planting events.

"It's a challenge," Simon acknowledges. "But if we can do it here, we can do it anywhere."

A Grow Greater Englewood Tree Ambassador learns to mark tree placement along with staff from the Morton Arboretum's Chicago Region Initiative. Photo courtesy of Raed Mansour.

Involving community partners

In 2019, Raed Mansour, who until recently was director of environmental innovation for Chicago's Bureau of Community Health, looked at tree canopy data for the city and discovered that some neighborhoods had as little as 4% to 8% canopy coverage. (American Forests cites 20% coverage in grassland cities and 15% in desert cities as "realistic baseline targets," with higher percentages attainable through increased investment and prioritization.)

The LEED Platinum city did already have a program in place that allowed citizens to request trees, but Mansour says that it often took up to three years for these requests to be fulfilled.

"I walked through communities, and I would see just blocks and blocks with no trees," says Mansour. "It was a surprise to people in government, but it wasn't a surprise to the community. They were already trying to get trees. It was frustrating for them."

In 2021, the city approved a $188 million environmental justice and climate action budget, which included $46 million to plant 75,000 trees over five years.

It was an aggressive target, Mansour acknowledges, but the city has made significant progress toward its goal-planting 55,000 trees in the first three years of the program-by proactively involving community members and organizations, some of whom had previously been mistrustful of city government due to a history of disinvestment in their neighborhoods. "When you have these disparities, people believe that government is not going to help them," Mansour says.

The city formed a tree equity working group, which over the course of three years grew from around 20 people to around 200, from nearly 70 different organizations. "One part of our strategy was to lower the barrier to participation," Mansour says. "The participants didn't need to be from a tree-focused organization. That allowed block clubs to come in, gardens to come in, small organizations, religious organizations."

"People who worked in social justice or in mental health or in housing-anyone could come in, and they did," Mansour adds. "Everyone had the same mission, to get trees where they were most needed."

Left: Fall 2023 tree planting along Boise Avenue by student volunteers from Timberline High School's TREE Club. Right: Boise Tree Captains and TVCN staff plant a tree with a homeowner in Boise's Vista Neighborhood, fall 2024. Photos credit: TVCN.

A tree for every household

According to legend, the LEED-certified city of Boise, Idaho, got its name from a French guide who shouted, "Les bois! Les bois!" ("The woods! The woods!") upon seeing the tree-lined Boise River after weeks of trekking through dry, rough terrain. Although it sits only miles from Boise National Forest, the city itself has a hot, dry climate, especially in the summer months, making it difficult for trees to thrive there without nurturing.

In 2013, the Idaho Department of Lands contracted The Keystone Concept, a land management and community development consultancy owned by Lance Davisson, to develop and manage a canopy study to learn more about the ecosystem benefits of the region's trees. At the time, officials were primarily concerned with air quality, but they hadn't yet given much consideration to urban heat. The study spurred the founding of the Treasure Valley Canopy Network (TVCN), of which Davisson is the executive director. As summers in Boise have grown hotter, the organization and city officials have paid more attention to the cooling effects of trees.

"Urban heat wasn't much of a consideration over 10 years ago, or at least people weren't measuring it when we started," Davisson recalls. "But after we had the canopy data, even though we didn't have urban heat maps yet, we started to recognize it was an issue."

Shortly after the study, the canopy network partnered with Idaho Power Company for a project that planted trees to the west of homes to help ratepayers reduce their energy consumption during peak hours in the summer. According to the utility, the 10-year program, which concluded in 2024, distributed a total of 21,000 trees across its service area. Over the next two decades, those trees are projected to save more than 30 million kilowatt-hours of electricity, filter more than 129 million gallons of stormwater and absorb more than 63,000 pounds of air pollution.

In 2020, the Treasure Valley Canopy Network partnered with the City of Boise for the City of Trees Challenge, an effort led by City Council President Elaine Clegg to plant one tree for each of Boise's 100,000 households by 2030. So far, the program has resulted in more than 19,000 tree plantings in Boise, as well as the planting of 235,000 forest seedlings (one for every Boise resident) in Boise National Forest.

"City Council President Clegg announced her vision for the City of Trees Challenge and partnered with the Network, we used our urban heat and tree canopy data to target the neighborhoods that need trees the most," Davisson says. "In order to effectively partner with these neighborhoods long-term, we developed the Boise Tree Captains Program that recruits community volunteers and trains them to plant and care for trees. These tree captains are a critical partner in working with our neighborhoods and homeowners to plan for, plant, and care for healthy trees across the community."

Boise Tree Captains and Treasure Valley Canopy Network staff plant a tree with a homeowner in Boise's Morris Hill Neighborhood, fall 2024. Photo credit: TVCN.

A nationwide effort

For the tree equity vision of American Forests to become a reality, says Hussain, cities across the U.S. will need to tackle the issue with the same strategic focus as Phoenix, Chicago and Boise-not only dedicating significant resources to urban reforestation, but also taking the time to get community members invested in the effort.

"When you have years and years of disinvestment in these communities-redlining and other forms of disinvestment-you create a lack of trust between community members and government," she says. "There have been many tree planting programs across the country that have not succeeded, because they were only about tree planting. You can't just pop trees into the ground."

Other American cities that are embracing strategic reforestation efforts include Louisville, Kentucky, where an initiative called the Green Heart Project planted 8,000 trees in a neighborhood, with plans to study associated human health outcomes; Houston, where an organization called Trees For Houston has planted a total of 700,000 trees since 1982, including more than 36,000 during the 2023-2024 planting season; and Mesa, Arizona, where city officials aim to plant 1 million trees by 2050.

"It's incredibly ambitious, and it's going to be very challenging, but the fact that it came from the mayor has made all the difference," says Simon, of Mesa's Trees Are Cool initiative, which was announced in February 2023. "That top-down approach doesn't work for everything, but when it comes to these big, ambitious goals, it's so crucial. When people are saying the city should plant more trees, it's not just them saying it. They can say, 'The mayor said to do this, so let's make it happen.'"

For a city like Mesa, where temperatures linger in the triple digits during the summer months, trees don't just make neighborhoods more comfortable, Simon argues. He says they make Mesa more livable-and, in the long run, perhaps even simply more viable.

"Businesses are seeing this," Simon says. "There's a lot of concern about whether, quite frankly, this area will be livable in 30 years, based on the way things are going. But when cities are making these big promises and these campaigns to plant a million trees, that gives businesses some assurance that this city is taking things seriously, and this might be a place where we can have our headquarters."

Such a decades-long view seems particularly appropriate when it comes to trees. Most people are likely familiar with the proverb, "The best time to plant a tree was 20 years ago. The second best time is now." It's a piece of wisdom that Varnadore, the LEED for Cities vice president who planted countless trees earlier in her career, has seen play out in real life.

"While you're planting the trees, you wonder if you're having an impact," Varnadore says. "Then you go back 20 years later, and there's this beautiful, functioning forest. You definitely think to yourself: I should have planted more."

Comments

Related articles

Related courses