Agroforestry supports food and nutritional security through : (1) the direct provision of tree food s such as fruit s and leaf y vegetables and by supporting staple crop production ; (2) by raising farmers' incomes through the sale of tree products and surplus staples ; (3) by providing fuel s for cook ing ; and (4) by supporting various ecosystem services such as pollination that are essential for the production of some food plants . While challenges for agroforestry in supporting food and nutritional security include policy and market constraints and an underinvestment in research , strong opportunities exist to promote multi functional , climate - smart agricultural methods involving trees . To better support food and nutritional security, development s in agroforestry policies are required to reform tree and land tenure for the benefit of s mall - scale farmers, to reform how smallholders obtain agroforestry inputs such as tree seed and seedlings , and to recognise agroforestry as an important investment option. Research should support tree domestication to improve the yields of tree foods , and seek to enhance the complementarity and stability of food production in smallholders' agroforestry systems.