Somerville has passed a Native Planting Ordinance that establishes minimum requirements for native plants and trees to be planted in city-owned parks, open spaces, and streets. The legislation, which applies to new plantings carried out by the city or on behalf of the city, grew out of discussions between the Administration, the City Council, and community advocates and passed unanimously in March.  

The Ordinance defines native plants and trees as those with origins in North America east of the Mississippi River. It requires that native species constitute 100% of all new plantings in any city-owned land on the Community Path, the Green Line Extension corridor, and riverfront areas; at least 75% of new plantings in city-owned parks; and at least 50% of street trees and new plantings in bioswales, plazas, streetscapes, and other city-owned property, subject to certain exemptions.   

Somerville’s policy is believed to be the first of its kind in any city because it includes percentage requirements for planting native species across all landscape types, whereas similar legislation in other cities encourages doing so but without a specific metric.  

While the city already plants large numbers of native plants in its parks projects, the new law ensures native plantings will continue to be prioritized where appropriate. It also codifies Somerville’s commitment to restoring and preserving native flora and fauna.   

“Protecting our natural environment is imperative both for our community’s long-term health and residents’ quality of life. Open space is precious in a densely populated city like Somerville, so we want to make sure we are creating the best green spaces possible,” said Mayor Joseph A. Curtatone. “I appreciate the passionate advocacy of residents around this issue and the City Council’s support and willingness to collaborate to create this Ordinance.”   

Plants sustain all living things on the planet, and native species in particular are foundational to healthy ecosystems because they provide food and habitat for native wildlife and pollinators like birds and insects. Pollinators are essential for pollinating our food crops and most other plants, and, without them,  the human race and most of the earth’s ecosystems could not survive. When planted in appropriate locations and under the right conditions, native plant species also may be able to grow easily once established and generally use fewer resources.  

“I’m proud to have proposed this Ordinance,” said Ward 7 City Councilor Katjana Ballantyne. “This achievement was a collaborative effort. This would not have happened without the expertise, tireless efforts, and passion from Renee Scott, Victoria Antonino, Brendan Shea, and David Falk. With this Ordinance, we lead the country in restoring our natural urban ecosystem.”  

Somerville’s Ordinance prioritizes planting native species while also accounting for the realities of current planting conditions and those anticipated in the future as a result of climate change. Some native plants and trees aren’t equipped to survive in Somerville today because they evolved thousands of years ago in an environment radically different from that of the modern-day city. Climate change will also bring hotter temperatures and more severe weather events, so any plantings installed now will need to tolerate more extreme heat, higher salt concentrations, and longer periods of flooding and drought in the future.  

“Non-native plants that are not invasive are also an important part of an urban ecosystem. We need to maintain a diverse planting palette to ensure the long-term health and survivability of our urban forest and our parks,” explained Senior Urban Forester and ecologist Dr. Vanessa Boukili. “Given that, it is really important to advance legislation that ensures native species will be a large part of our ecosystem while still allowing for some flexibility in plant selection, and I think that’s where this Ordinance really succeeds.”  

“Working with advocates and the Council has led to legislation that is nuanced and practical – it moves the needle forward on an important ecological goal and still allows the city to manage a municipal planting system and urban forest,” said Luisa Oliveira, Director of Public Space and Urban Forestry. “In an urban environment like ours, there is a balance between finding plants and trees that will survive in the harshest conditions and planting native species that provide habitat for native birds and pollinators. This Ordinance ensures that, above all, the right plant can be selected for the right location.”  

— City of Somerville