Portland trees have been working overtime in the past few years providing benefits to the residents of Portland, people, and animals alike. From storm water remediation to providing shade during heat waves, Portland’s trees continue to keep our city livable. With the increase in invasive pests and diseases, our city trees need our support more than ever.
A new dawn: investing in urban forest care
But help is on the way. A new five-year investment recommended by the Portland Clean Energy Community Benefits Fund (PCEF) Committee will enable the City to take over the planting, establishment, pruning, removal, and other needed care of Portland street trees—generally, those planted on the strip between the road and sidewalk. If approved as expected during city budgeting this spring, the plan opens a tremendous opportunity to repair and expand the city’s tree canopy in ways that help residents cope with climate change.
PCEF Green Infrastructure Lead David Grandfield has spent almost a decade in roles that help the city improve its connection to nature. “The tree canopy can create microclimates that reduce temperatures by 15 to 20 degrees. The investments we’re making and the species we’re selecting will help Portlanders in the future survive these heat events.”
And by choosing appropriate trees and caring for them correctly, the city can prepare the revitalized urban forest to better survive harsh winter storms, Grandfield said.
The science of trees: natural solutions to climate change
Science has demonstrated many reasons trees are essential to human and environmental health. Tiny pores on their foliage, called stomata, help filter air, removing pollutants that harm our health. Tree roots purify stormwater and help recharge groundwater. And when it comes to fighting climate change, trees are champions. They store carbon in their roots, trunks, and limbs as they grow.
During each warm season, new leaves pull more carbon from the atmosphere. National Geographic described the foliage on the earth’strillions of trees as an “unimaginably vast planetary breathing system – a giant green machine that pulls enormous quantities of carbon dioxide out of the air, especially in the warmer months.”
Disparities in tree canopy: addressing inequity
On the ground, trees planted in the right spots can cool the area around them by shading surfaces, deflecting radiation from the sun, and releasing moisture. But in Portland, as in other parts of the country, trees tend to be concentrated in wealthier areas. A Portland State University study showed households with the top 20% of incomes had 20% more tree canopy than those with the lowest 20%– which also tended to be neighborhoods inhabited by immigrants, refugees, and communities of color. On Portland’s west side, canopy cover is 46%, excluding Forest Park. On the east side, canopy cover is only 22%.
In poorer neighborhoods, fewer trees and more buildings and pavement can drive heat wave temperatures to unbearable levels. During the June 2021 heat dome that killed at least 69 people in Multnomah County, 42 occurred in neighborhoods known to experience heat islands.
Funding green futures: the role of the Portland Clean Energy Community Benefits Fund
PCEF exists to help Portlanders deal with climate change. A tax on large retailers provides a consistent, long-term funding source for the City’s climate goals, ensuring that all Portlanders – especially people with low incomes and communities of color – can cope. About 10-15% of the fund goes toward green infrastructure and regenerative agriculture, Grandfield said. Expanding and strengthening Portland’s tree canopy for intense weather is a natural fit.
Under the PCEF Committee recommendation, Portland's more than 250,000 existing street trees and street trees planted in the future would be cared for by Portland Parks & Recreation, Urban Forestry Division. Every street tree will be placed in a routine management cycle of inspection, structural pruning, hazard abatement, removal, and replacement. Several aspects of Portland’s program will set these trees up for long-term success, Grandfield said. They include:
- Caring for and maintaining trees. Routine care by skilled providers will reduce public safety hazards, maximize the services trees provide such as lower summer temperatures and improved air quality, and help trees have longer productive lifespans.
- Choosing diverse and appropriate trees to plant, focusing on high-need areas to enhance survival against pests, pathogens, and extreme weather. They will diversify Portland’s street tree species to include more types.
- Searching out the highest quality plants, Grandfield said. An array of nurseries will supply saplings, and workers will scrutinize young trees to ensure they are hardy, with unscarred trunks and healthy branch and root structures. Since a tree’s long-term health depends significantly on the skilled planting, pruning, watering, and mulching it receives in its first five years, the new program pays for that care.
- Fostering a connection between residents and urban trees through volunteer opportunities, outreach, and education on tree care, benefits, and identification. The program educates Portlanders on how to care for trees in their neighborhood, including avoiding trunks when mowing and managing the spread of invasive species like Tree of Heaven.
After facing winter storms, heat domes, and invasive species, PCEF’s investment in Portland’s tree canopy marks a proactive shift from climate adversity to resilience. By revitalizing its urban canopy, Portland will craft a tomorrow where green spaces curb climate impacts, bridge social divides, and enhance urban living. This program can serve as a blueprint for cities worldwide to follow, demonstrating that investing in nature is investing in the future.
Learn about grantees and their projects from the first grant cycle: RFP #1 Project Descriptions
Learn about grantees and their projects from the second grant cycle: RFP #2 Project Descriptions