Societal Impact Statement
Modern food systems push agriculture to focus on a small number of commercial crops, while there is a very large diversity of untapped edible plants that could be used to address food security and nutrition. Poor and monotonous diets are closely linked to the complex burden of multiple forms of malnutrition and dietary risk. In some contexts, such as West Africa, micronutrient deficiency risks are particularly pronounced. Hence, there is an urgent need to provide people with healthy diets supported by sustainable food systems. Within this context, using nutrition-sensitive forest landscape restoration to combat environmental degradation could contribute towards ensuring the year-round availability of nutritious tree-based food.

Summary
Diverse diets are important to deliver adequate amounts of the nutrients essential to human health. The consumption of a diversity of food groups is challenging in sub-Saharan Africa. Trees play an important role in the direct provision of nutritious food items. Forest landscape restoration presents an opportunity to reverse the loss of useful trees, due to degradation, and increase representation of food tree species in the landscape.
Here we focused on characterizing the contributions that different food products from trees can make to improving diet diversity in Burkina Faso. A scoring system was developed, based on seasonal availability of edible products and food groups covered, and was integrated into a freely available decision-making tool that enables carrying out context-specific, optimal choices of tree species to be considered in forest landscape restoration.
Our inventory included 56 food tree species, largely Fabaceae (18 species), providing 81 edible products, mainly fruits (supplied by 79% of tree species), followed by seeds (52%) and leaves (41%). The main food groups represented are ‘Other fruits’ (other than vitamin A-rich fruits) (covering 52% of the edible products) and dark-green leafy vegetables (29%). About two thirds of the species listed produce more than a single edible product, a few up to four. A total of 11 species supplied edible products throughout the year.
Our results clearly show that seasonal scarcity of food and nutrients in Burkina Faso can be partly mitigated by consuming edible tree products. The methodology can be easily scaled to other geographies.

decision-making tool, nutrition security, sub-Saharan Africa, underutilized tree species, wild tree species