Gracie Villa


Masters in Landscape Architecture Thesis Prize

City | Forest: Reordering Plant-Human Relationships Toward Healthy Cities

Advised by Gary Hilderbrand

Based in the belief that the quality of the urban landscape directly reflects the quality of its soil, I propose to utilize processes of beneficial disturbance to reorder the vegetative and soil regimes in the city’s public realm. The outcome is a regenerative living infrastructure identified as the City Forest; a collection of trees, associated undergrowth, and soil where people live, work, and play. This topology offers an alternative to the objectified street trees that make up most of America’s urban vegetation and curates an intensive dialogue between people and forest, or city and forest, not possible under current spatial practices. 

In this case study, the City Forest redefines major corridors in Cambridge, Massachusetts, as an efficacious place to begin intensifying the forest. Cambridge is a leader in urban forestry but has yet to boldly confront the socioeconomic practices inhibiting a healthy future. By rejecting the hierarchies and land use patterns inherent to our car-centric landscapes, the City Forest emphasizes solidarity with nonhuman nature and advocates against destructive forms of economic practice and ontological distinction, asserting that the natural capital that accumulates in the forest reciprocates directly with healthy lived experience in the city.

Aerial view of a city landscape showing trees interspersed with buildings.
The City Forest is a collection of trees, associated undergrowth, and soil where people live, work, and play. This aerial shows the City Forest along Massachusetts Avenue and Cambridge Street and reveals how the proposal will connect and expand the urban vegetation throughout the city.

Map of the City of Cambridge showing lines depicting Forest Corridors.
This city plan identifies the primary and secondary corridors in the City Forest proposal. As a regenerative infrastructure, the City Forest is also a political movement. By utilizing processes of beneficial disturbance to dismantle the city’s most prominent built infrastructure, the City Forest reorders the vegetative and soil regimes across the public realm.

Collage of photographs showing trees in an urban landscape.
As a physical space and political movement, the City Forest represents a relational way of being that requires solidarity. This collage represents the reciprocity that the City Forest strives to produce.

Section diagrams of proposals for lanes of traffic on Massachusetts Avenue.
These sections show how the City Forest will transform the street section. In the City Forest, soil and the lived experience take center stage while private vehicles are excluded, leaving only a 20’ dedicated bus lane, which will always be required for transit and life safety.

A series of five plans showing bicycle and pedestrian lanes on a major city road.
The City Forest prioritizes pedestrians and cyclists. These plans highlight the new pathways that will define the shared street. Starting on the left, a 2-way dedicated bike path, a beeline for pedestrian thru-traffic, sweeping traverses for diagonal movement, crossovers for quick access to storefronts, and a meandering path for lingering shoppers.

Chart showing lists plant species suitable for groundcover, shrubs, subcanopy, and canopy uses.
The City Forest planting palette will help the city plant species most adapted to the different environments throughout Cambridge, and ensure that the species selected are visually and texturally interesting, as well as ecologically significant to the non-human species that will encounter them – including birds, pollinators, soil microbes, and small mammals.

Map of the City of Cambridge showing areas of different ecotypes: lowlands, low-uplands, and uplands.Map of the City of Cambridge showing areas of different ecotypes: lowlands, low-uplands, and uplands.
This city plan lays out all three ecotypes, from lowlands to low-uplands to uplands. This map is intended to guide how different sections of the proposal are planted out as it is implemented. These zones are based on precipitation and flooding projections produced by the City of Cambridge.

Photograph of a city boulevard taken from the sidewalk next to a rendering of the same view with copious vegetation added and a bicycle lane.
The City Forest will be planted in three phases. The first includes larger trees, shrubs, and plugs in the most visited parts of the public realm, such as Central Square.

Photograph of a fire engine on a city boulevard next to a rendering of the same view with trees, pedestrian crossings, and a bicycle lane.
The City Forest will transform Massachusetts Avenue into a shared street. Without curbs, stormwater can sheet into the permeable ground and ensure access for all throughout the space.

Photograph of an ambulance on a city boulevard with separated bicycle lane next to a rendering of the same view with expanded sidewalk and vegetation.
Along Cambridge Street, two-way traffic will remain in place while the City Forest fills in sections on either side. Here, the existing parking spaces and bike lane remain intact to ensure less centralized businesses remain viable.

Photograph of pedestrian crossing on a wide city boulevard next to a rendering of the same view with added vegetation on the sidewalk and a large designated pickup area for vehicles.
Here, an alternative City Forest layout takes advantage of the existing conditions. Many of the species used in phases two and three are pioneer species, which grow quickly and create an environment that welcomes secondary growth. The introduction of flex zones will ensure buses, ride-share services, and delivery services can still serve the community.

Chart showing action plan and projected timelines.
Resilience, use, and equity are all key themes in the Healthy Forest, Healthy City report. As a result, the city’s action plan created a framework for the City Forest Implementation Plan. That action plan lays out 9 initiatives to be completed by 2025, and the City Forest’s implementation will fold into and ultimately expand 4 of them.