Where the wild things are: How urban foraging and food forests can contribute to sustainable cities in the Global North

Humanity is faced with interacting socio-environmental challenges such as securing food while the climate changes and biodiversity declines. These global crises are partly caused by major land-use change arising from deforestation and agriculture, and are exacerbated by the high demand for resource-intensive foods from populations in the Global North, which are increasingly concentrated in urban centres. The demand by urban populations on the food system has stimulated research on developing sustainable and healthy sources of food within cities. However, debates largely focus on typically treeless urban agriculture and tech-food approaches. This bias neglects the pivotal role of trees and shrubs for ecological and cultural ecosystem service provision, and thus the multifunctional potential of foraging "wild" foods or "semi-wild" cultivation such as in designed food forests in or near cities. In a wide, emerging, and multidisciplinary research field, the actual or potential contribution of urban woodlands to food security and other societal needs such as carbon sequestration and habitat provision often remains taken-for-granted, implicit, or ambiguous. To evaluate the extent to which urban food forestry in the Global North may generate socio-ecological win-win outcomes for climate, biodiversity and society, we review evidence from natural and social sciences along four analytic dimensions: (1) climate change, (2) biodiversity, (3) food production, and (4) relational aspects. Our findings demonstrate the multifactorial benefits of urban foraging and food forestry, but also flag potential risks and disservices ascertained in the literature. We use the synthesised evidence along these dimensions to identify existing gaps and future research directions for optimising socio-environmental benefits. We conclude that much is to be gained from upscaling spaces "where the wild things are" but that requires certain systemic changes to be taken seriously.