In celebration of Arbor Day, Gov. Maura Healey on April 26 announced a new program to expand tree planting in environmental justice communities across Massachusetts.

Cooling Corridors will prioritize projects that help reduce local heat islands, facilitate urban heat mitigation, and increase the regional tree canopy.

Cooling Corridors will complement Greening the Gateway Cities, which operates in 23 of 26 gateway cities across the state to increase the urban tree canopy. Cooling Corridors will target environmental justice communities outside of gateway cities that are contending with extreme heat and poor air quality.

Healey was joined by Energy and Environmental Affairs Secretary Rebecca Tepper, Department of Conservation and Recreation Commissioner Brian Arrigo, and Chicopee Mayor John Vieau at an elementary school in Chicopee to celebrate the 40,000th Greening the Gateway Cities-planted tree and announce the new Cooling Corridors program.

“Our Greening the Gateway Cities program and the new Cooling Corridors initiative help bring down the temperatures in urban areas, saving residents energy costs, increasing property values, and creating good-paying local jobs,” Healey said.

Lt. Gov. Kim Driscoll added that tree planting is “the only energy-efficiency program where almost all of the investments stay in the local economy” through the hiring of local planting crews and planting of trees from local nurseries.

Cooling Corridors will support tree-planting initiatives by municipalities, nonprofits and other organizations. The program will target walking routes in areas that suffer from extreme heat, such as urban heat islands and hotspots, within environmental justice neighborhoods.

Greening the Gateway Cities began in Chelsea, Holyoke and Fall River, and has expanded into 23 of the original 26 gateway cities. Trees are planted by the DCR with crews hired from local communities. The program plants trees ranging from six feet to 10 feet in height, with a goal of covering 5% of the target neighborhoods in new tree canopy cover.

In high-density urban neighborhoods, planting an average of five trees per acre (roughly one third of a block) will provide benefits to 15 to 25 households, depending on building density. Planting this number of trees will increase canopy by an estimated 1% in eight years and 5% in 30 years.

Tree planting is an important strategy as the climate warms. Trees near a home provide shade to structures, significantly lowering surface temperatures, while trees up to 1,500 feet away from a home still provide a benefit. Additionally, in the winter months, mature tree trunks and branches help to randomize wind patterns and decrease heat loss by air infiltration in poorly insulated homes.