No Produce Left Behind: Measuring Farm-Level Food Loss
To tackle the twin problems of on-farm food loss and local food insecurity, multidisciplinary student teams worked with faculty and staff members to develop reliable estimates of unharvested, edible produce in order to help food banks provide nutritious food assistance as well as reduce the environmental impacts of farming.
Call to Action
The long-standing collaboration between the Leavey School of Business’s Center for Food Innovation and Entrepreneurship (CFIE) and Second Harvest Food Bank led to discussions about capturing a portion of the food that goes unharvested in nearby farming valleys for distribution to the food banks. The food bank has a great need for fresh produce, which is a critical component of a healthy diet. However, fresh produce tends to be a very expensive source of calories. The lack of sufficient fresh produce is also viewed as contributing to unhealthy diets and the obesity problem for food assistance recipients. Silicon Valley, with a large urban population and high proportion of families that are food insecure (27 percent), is located in close proximity to two of the world's most productive agricultural regions, Salinas Valley and California's Central Valley.
Colleagues at the food bank suggested that it would be helpful to understand the availability of unharvested fresh produce as a potential low-cost source of nutritious produce for food bank clients. CFIE also worked closely with the World Wildlife Fund (WWF), which is interested in the sustainability implications of food loss. In addition to providing financial support for the project, the CFIE hosted a food loss conference with WWF. We undertook the project because we believed that it was important both for food banks and because of the sustainability implications. Furthermore, CFIE had the expertise, resources, and industry connections needed to successfully conduct the research.
Prior to starting the project, most estimates of farm-level food loss were based on questionnaires or interviews of growers. No major study had examined farm-level food loss by actually conducting in-field measurements, which we believed were critical to providing accurate estimates. Our principal objectives were to measure the amount of unharvested, edible produce for multiple crops, to compare measured amounts to grower estimates, and to understand the principal causes of farm-level food loss.
To carry out the project we assembled a multidisciplinary team, with expertise in agriculture, economics, and sustainability. The research involved developing protocols to collect, classify, and measure unharvested produce. We hired and trained teams of undergraduate students who were willing to awaken early, travel, and do the hard field work of collecting, weighing, and recording the unharvested produce. Because the protocols were different for every crop, the students were intimately involved in developing crop protocols.
In the summers of 2016 and 2017 we surveyed 20 crops in 123 fields. Follow-up interviews were conducted in 2018 to account for fields that are never harvested (walk-by fields). The data were analyzed and the results constitute the most comprehensive measure of on-farm food loss to date.
We found that farm-level food loss is an average of 33 percent of marketed produce (25 percent of what is produced). For most crops, this translates to several tons per acre of edible produce that will be plowed back into the soil. We also found that most growers grossly underestimate the amount of produce left in their fields. On average the actual amount left unharvested was about two and a half times what growers estimated. This finding should cause researchers to reevaluate the results and methods used in previous survey-based research. The high level of food loss is both astounding and disheartening, especially given the level of food insecurity experienced in the U.S.
Understanding the magnitude of the loss should motivate new work to better utilize the unharvested produce as well as to better align production with consumption. The possibility of concurrent harvesting, that is harvesting produce for both the market and for food banks, may offer a solution to food banks that are working to affordably improve the nutritional content of the foods they provide to their clients. This is an especially good alternative for food banks located near major produce-growing regions. Modern agriculture represents an intense use of land, water, fossil fuel, chemical, and labor resources. Creative solutions to better align production with consumption, while accounting for the inherent variability in agriculture, offer promise to conserve vast amounts of these resources.
Second Harvest Food Bank of Santa Clara and San Mateo Counties; Santa Clara University Department of Environmental Studies and Sciences; World Wildlife Fund