Fighting urban heat with more trees

Alex Brown

THE WASHINGTON POST – As the Pacific Northwest sweltered through a recent record-breaking heat wave, many residents here in America’s least air-conditioned city sought relief under the shade of cedars and maples in city parks. But in some areas of Seattle, that shelter was hard to come by.

“If you look at aerial photographs, north Seattle looks like a forest,” said Washington state Representative Bill Ramos, a suburban Democrat who sponsored a bill the legislature recently passed to help cities improve their tree canopy.

“On the south side, you see nothing but rooftops and asphalt and not a green thing anywhere. It’s strictly a matter of socioeconomics and race.”

That disparity is not unique to Seattle. Washington DC-based conservation non-profit group American Forests released a nationwide analysis last month showing that low-income neighbourhoods and communities of colour have significantly less tree canopy. Those areas also are more likely to suffer from the urban heat island effect caused by a lack of shade and an abundance of heat-absorbing asphalt. Heat islands can be as much as 10 degrees hotter than surrounding neighbourhoods.

“We found that the wealthiest neighbourhoods have 65 per cent more tree canopy cover than the highest poverty neighbourhoods,” said the group’s vice president of urban forestry Ian Leahy. “As cities are beginning to heat up due to climate change, people are realising that trees are critical infrastructure. I’ve never seen as much momentum toward urban forestry across the board.”

A conservation non-profit group released a nationwide analysis last month showing that low-income neighbourhoods and communities of colour have significantly less tree canopy. PHOTO: AP
Seattle cityscape

In many cities and states, policymakers and advocates said they’re aiming to correct decades of inequities in urban tree canopy.

They acknowledge how racist policies such as redlining have had a stark effect on the presence of urban green space, and that trees are important for public health. Some leaders have even pledged to use American Forests’ “Tree Equity Score” to target their tree plantings in the neighbourhoods that need it most.

“People weren’t thinking about trees as these resources that provide a lot of benefits,” said urban forestry coordinator with the Michigan Department of Natural Resources Kevin Sayers. “They thought of them as niceties, and trees followed money. There’s now a recognition that trees were not equitably distributed and maintained.”

Sayers works to help cities and nonprofit groups manage and improve urban forests. Michigan’s 10-year Forest Action Plan, which was drafted last year, calls for a neighbourhood-by-neighbourhood tree canopy analysis, with the goal of reaching equity. Sayers said he will work to incorporate the new tree equity data into that plan.

In many places, efforts to increase urban tree canopy are still in their early stages. Officials are conducting surveys, setting goals and making plans – while acknowledging the real work is still ahead. They said it will take time to build trust in underserved communities, scale up planting programmes and change local laws to protect existing trees. But long-time foresters said political buy-in for such efforts has never been higher.

Trees provide important public health benefits, starting with the cooling shade they provide. A study published last year in the journal Environmental Epidemiology found that heat causes thousands of excess deaths in the United States (US) each year, far above official estimates. City and state leaders expect climate change to worsen the threat.

“Trees are nature’s air conditioners, and we’re starting to talk about them as a real adaptation investment,” said Managing Director at the Rhode Island Infrastructure Bank Shaun O’Rourke, who also serves as the state’s chief resilience officer.

The state has worked with 20 municipalities in its programme to fund climate resilience projects, and all of them have sought more resources for urban tree planting, O’Rourke said. Meanwhile, the Rhode Island Department of Health has incorporated tree canopy data into its health equity indicators, putting it alongside categories such as health-care access and food insecurity.

“The data shows that Latinos and African Americans have a higher likelihood of dying after five days of extreme heat, and that’s an injustice,” said Chief Executive Cindy Montañez of Tree People, a non-profit organisation that works on planting and education projects near Los Angeles. “Planting trees is not about carbon reduction, it’s about saving lives.”

Los Angeles has appointed its first city forest officer to coordinate the city’s urban forestry efforts across departments. Rachel Malarich, who took the job in 2019, has been tasked with increasing tree canopy in underserved neighbourhoods by 50 per cent by 2028.

“Nineteen per cent of all the tree canopy cover in Los Angeles exists where one per cent of our population lives, concentrated in these affluent areas,” Malarich said. “The conversation has changed, and there are more public officials recognising that tree canopy is not a beautification measure, but a central piece of our infrastructure.”

Trees also help to filter pollution from the air and absorb storm-water runoff. Studies also have shown that the presence of trees can have positive effects on mental health and cognitive function.

Earlier this year, the Phoenix City Council voted to partner with American Forests to create an equitable tree canopy across all of its neighbourhoods by 2030. The city has identified the busiest walking corridors where shade could prove most beneficial, and it’s planning to plant 1,800 trees along nine miles of “cool corridors” each year.

In Boston, researcher and advocate Neenah Estrella-Luna is serving as a consultant to help draft the city’s first urban forest plan. Her team is working with city officials and community leaders to develop a pathway to tree equity in 20 years.

“The folks most marginalised – people of colour, immigrants and low-income people – have the least access to anything green,” she said. “This is clearly an issue of environmental justice.”

Some state lawmakers have been active on the issue, as well. Ramos introduced a bill this year that will require Washington’s Department of Natural Resources to conduct a statewide assessment of urban tree canopy to find where it’s lacking.

The measure, which was adopted by large, bipartisan majorities and signed into law, will also allow the agency to provide technical assistance to local governments for forest management. Half the money must go to underserved communities.

“We know trees create better health,” Ramos said. “How can we say that some people should have trees and other people shouldn’t?”

In California, State Assembly member Luz Rivas, a Democrat from the San Fernando Valley, has sponsored a bill that would create a funding programme to help communities adapt to extreme heat. Projects could include urban forestry and green spaces. The bill passed overwhelmingly in the Assembly and is under committee review in the state Senate.

State and local leaders acknowledge that reaching tree equity won’t be easy or simple. Many urbanised areas lack suitable places to plant, especially spots that can accommodate the large trees that provide the biggest benefits. Also, most urban trees grow on private land, meaning cities cannot rely only on parks and streets to reach their goals.

In many neighbourhoods, cities have done a poor job of maintaining existing trees, which can damage houses and cars if unhealthy trees are left to fall. That has made some residents skeptical about new plantings.

“Tree planting is always a very visible thing, but nobody likes to give due recognition to tree maintenance,” Sayers said.

Even in cities with strong tree planting programmes, leaders have found they are still losing canopy cover each year as urban sprawl and development uproots existing trees to make way for housing. Forestry experts said cities need strong tree protection ordinances to have a chance of reaching their goals.

Foresters said their programmes are often understaffed, and they are some of the first to face cuts during difficult economic times. Urban forestry coordinator with the Delaware Forest Service Kesha Braunskill said tree equity programmes need to have a stronger workforce and a consistent presence in the areas they’re trying to reach.

“We need more of us, and more of us that look like the communities we serve,” she said. “We have to formulate relationships. We can’t just walk in, plant a tree and walk away.”