12/09/2025 | News release | Distributed by Public on 12/10/2025 05:14
Megan Ryder (SPH'25) on planting day at Boston Green Academy in Brighton, Mass., October 3, 2025.
Miyawaki forests-which involve planting dense layers of native species in small urban environments-have popped up around the world since they were popularized by Japanese ecologist Akira Miyawaki in the 1970s.
Now, thanks to the work of Boston University graduate student Megan Ryder, you can view one just a couple of miles from campus.
Ryder (SPH'25), who works as a research assistant at BU's Chronic Traumatic Encephalopathy Center, is also earning an MPH in epidemiology and biostatistics. Last spring, she won first place in the 2024 BU Climate Innovation Challenge for her project pitch: planting a Miyawaki forest at a local Boston school in need of more green space.
This fall, she partnered with nearby Boston Green Academy (BGA), a 6-to-12 charter school just outside of Brighton Center. On October 3, students in a BGA technical environmental science class helped Ryder plant a 17×36 foot Miyawaki forest, featuring nearly 150 species of shrubs, trees, and flowering plants, on their campus.
Green spaces have long been shown to curb the urban heat island effect, a phenomenon where concrete and buildings trap and store heat and make the surrounding area warmer. The layers of plantings in a Miyawaki forest mimic a natural forest, from ground covers to tree canopy. The densely populated forest is designed to grow at a faster pace and absorb more carbon than other planting methods. More carbon in soil means less carbon in the atmosphere, warming the environment.
Green space isn't distributed equally across Boston's neighborhoods. "You can see from data that the City of Boston collects that there is a lot more green space in more affluent neighborhoods," Ryder says. "The ultimate goal of this project was to mitigate urban heat island effects for a population of people that need it."
The project required intense planning and proved to be physically demanding. Prior to planting, Ryder tilled the plot. She and the school invested in high-quality fungal microbes, which help establish a communication network between tree roots, to mix into the soil. (The school helped cover the cost of trees, too, she says.) She also installed a drip irrigation system. On planting day, Ryder oversaw the planting as students followed a specific grid system: one tree, one mid-layer plant, and one ground coverage plant per square meter. BGA, which Ryder says was an incredible partner in the project, will be responsible for all maintenance going forward.
BGA students planted everything in a grid system: one tree, one mid-layer plant, and one ground coverage plant per square meter.
She credits multiple local landscapers with helping design and execute the micro-forest. Architect Aaron Kraemer, designer of a Miyawaki forest in Brookline, provided her with the species list he used. Ryder sourced plants from Wagon Wheel Farm Stand and Plant Nursery in Lexington and she says the nursery's arborist, José Yurrita, was indispensable in helping her figure out the layering. And an arborist from landscaping service Hartney Greymont came to BGA and led a tree-planting tutorial for students ahead of planting day.
"We had a lot of friends help us along the way," Ryder says. "People really invested in the project; it was incredible how much kindness there was. It just made me want to give back even more."
Miyawaki forests have myriad positive impacts. Beyond the cooling effects and carbon sequestration, they also increase the biodiversity of an area, improve water absorption-which can buffer flooding-and reduce air pollution. The micro-forests are also self-sufficient: they require no weeding or watering after the first three years.
Plus, the Brighton forest is educational: every week, students measure close to 20 different variables about the forest, such as air quality and temperature. The funds Ryder received from winning the Climate Innovation Challenge also allowed her to partner with the University's innovation and experiential learning lab BU Spark! to build an accompanying app, which, when launched (the goal is sometime this month), will use the student-collected data to track the forest's long-term impact.
Going forward, BGA students will collect data from the Miyawaki forest to track its long-term impact. "This project is empowering students to engage in science," Ryder says.
"This project is empowering students to engage in science," Ryder says. "Not only are they learning about what environmental justice is, but they're benefiting from having this environmental intervention at their school and learning these hard skills that they can use in a future career in environmental science."
Ryder's interest in the environment traces back to growing up in the shadow of the Santa Cruz mountains. Learning about concepts like social determinants of health-or how nonmedical factors like income and environment influence individual health outcomes-in her SPH classes has only strengthened her commitment to environmental justice.
The micro-forest feels like a good starting point-for both her and the next generation of environmental scientists. "I not only wanted to give these people [the green space] they deserve, but I also wanted to give them the tools to be able to engage with it in a tangible way," Ryder says. "There was this really beautiful evolution from the pitch contest to the actual implementation."
This School of Public Health Student Designed a Micro-Forest in Brighton