UC Berkeley

Urban agriculture has enjoyed renewed popularity across North America over the past few years due to a vibrant food justice movement challenging disparities in access to healthy food, as well as to municipal policy and planning efforts focusing on urban sustainability and public health. Using qualitative and quantitative methods, this dissertation links critical political economic analysis and practical, action-oriented research grounded in community engagement to uncover the historical and geographic conditions necessary for the rise of a vibrant urban agriculture movement in Oakland California. In addition to being critical and reflective, this dissertation is also prescriptive in its examination of urban agriculture's potential to scale up in way that contributes significantly to food justice and urban sustainability. These two tasks mark the division of the dissertation into two equal parts comprised of three chapters each. Broadly, Part 1 (Origins) examines the historical and contemporary conditions, both necessary and contingent, that have given rise to the current urban agriculture movement in Oakland. In Chapter 1 I use the theoretical framework of metabolic rift (which I disaggregate into three interrelated forms: ecological, social, and individual) to explore the multiple origins of urban agriculture as a global phenomenon and demonstrate how it arises in response to the upheavals and alienation inherent to a capitalist political economy. In Chapter 2, I argue that understanding urban agriculture in Oakland today requires examining the city's uneven development. Through a historical overview of Oakland's economic geography from the early 20th century to the dawn of the Neoliberal era, I explain how the "demarcated devaluation" of industrial and commercial capital concentrated poverty in the city's flatlands and diminished food access for low-income people of color. In Chapter 3 I explain how the contemporary urban agriculture movement arose in response to this devaluation. Through a relational history linking seminal moments of flatlands activism (the Black Panther Party's Free Breakfast Program, the environmental justice movement, and a social justice-oriented urban greening movement) to the contemporary food justice movement, I reveal how a multi-racial, cross-class alliance was formed around urban agriculture which was able to contest the material implications of flatlands devaluation in new political arenas, marshalling financial support. These scalar politics have led to urban agriculture's increased institutionalization and ongoing policy efforts to scale it up. Part 2 (Obstacles and Opportunities) addresses the environmental and policy obstacles that must be addressed before such scaling up of urban agriculture can take place. Drawing on participatory methods, the three chapters in this part address specific technical questions defined in collaboration with community members. In Chapter 4 I present a GIS-based inventory of potential urban agriculture sites and calculate their potential contribution to vegetable consumption in Oakland. Overall, the inventory identified more than 800 acres of publicly owned land that could potentially be used for food production. Devoting 500 acres to urban agriculture could contribute 19 to 48% of current vegetable consumption in Oakland (or 6 to 15% of recommended consumption) depending on production methods. In Chapter 5 I evaluate the extent to which soil lead (Pb) contamination may be an obstacle to the expansion of urban agriculture in Oakland. I use a combination of GIS and spatial statistics to characterize the spatial distribution of Pb on vacant land at multiple scales across Oakland and to identify relationships between soil Pb levels and anthropogenic factors such as zoning, housing stock, roads, airport, and land use, as well as biophysical factors such as soil series, soil chemical characteristics, and vegetative cover. I also assess the extent to which total soil Pb is actually available for plant uptake. Using samples collected in the field and two greenhouse experiments, I evaluate two chemical extractants (DTPA and MgCl₂) in an effort to identify the best proxy for plant available Pb and to relate plant availability to a suite of soil chemical characteristics. While soil Pb levels were significantly higher in West Oakland and residential areas than other parts of the city, levels were generally lower than federal screening levels of 400 parts per million. Old housing stock (and lead paint) proved to be the primary anthropogenic factor affecting soil Pb levels, while soil phosphorus proved to be the most important chemical factor. In Chapter 6 I focus on the policy obstacles to the scaling up of urban agriculture through a case study on the efforts of the Oakland Food Policy Council (OFPC) to develop new zoning definitions and operating standards for urban agriculture. Ultimately, pressure on City Council members by the OFPC, as well as public pressure following two high profile events (the passage of an urban agriculture ordinance in San Francisco and the citation of a prominent urban farmer for zoning violations), were necessary to motivate planning officials to update urban agriculture zoning in Oakland. I conclude with the observation that while the technical obstacles to urban agriculture's expansion may easily be overcome, political obstacles remain. Furthermore, urban agriculture alone cannot feed a city such as Oakland or mitigate unequal access to healthy food, but rather must be part of a coordinated push for regional equity that addresses all aspects of the food system, from production to processing, distribution, and retailing.