Agroforestry refers to any of a broad range of land use practices where pasture or crops are integrated with trees and shrubs. This intentional combination of agriculture and forestry has multiple benefits, such as greatly enhanced yields from staple food crops, enhanced farmer livelihoods from income generation, increased biodiversity, improved soil structure and health, reduced erosion, and carbon sequestration. Trees in agroforestry systems can also produce wood, fruits, nuts, and other useful products with economic and practical value. Agroforestry practices are especially prevalent in the tropics, especially in subsistence smallholdings areas with particular importance in sub-Saharan Africa. However, due to its multiple benefits, for instance in nutrient cycle benefits and potential for mitigating droughts, it has been adopted in the USA and Europe .
Agroforestry shares principles with intercropping but can also involve much more complex multi-strata agroforests containing hundreds of species. Agroforestry can also utilise nitrogen-fixing plants such as legumes to restore soil nitrogen fertility. The nitrogen-fixing plants can be planted either sequentially or simultaneously.
According to Paul Wojtkowski, the theoretical base for agroforestry lies in ecology, or agroecology. Agroecology encompasses diverse applications such as: improved nutrient and carbon cycling; water retention of soils; biodiverse habitats; protection from pest, disease and weed outbreaks; protection of soils from water and wind erosion, etc. From this perspective, agroforestry is one of the three principal agricultural land-use sciences. The other two are agriculture and forestry.
There is still not enough data to determine the full range of the impacts and benefits varying agroforestry practices could have. The indigenous practices that form the inspiration and basis for agroforestry are frequently complex, including a large array of species. The most studied agroforestry practices involve a simple interaction between two components, such as simple configurations of hedges or trees integrated with a single crop.