Agroforestry, the deliberate integration of woody species with agricultural crops or pastures, is an ancient practice that is coming back into vogue. In Europe, farmers used to integrate apple orchards with sheep pasture, and timber or nut trees with cereal crops. In tropical latitudes, farmers imitated vertical forest structure and diversity by planting a variety of crops with different growth habits. At one time, it was not unusual to find up to 24 species planted on a tenth-of-a-hectare plot, with each crop mimicking the layers of a tropical forest. In the tropics, agroforestry land management practices maintain landowner self-sustenance, whereas in temperate latitudes, the focus is on resource management, farming technology, labour costs and real-estate values. In both temperate and tropical conditions, however, trees are an integral part of an agroforestry system that can rejuvenate marginal lands, maintain soil fertility and crop productivity, and mitigate climate change. Each hectare of sustainable agroforestry production in tropical latitudes can prevent up to five hectares of deforestation. As such, agroforestry helps maintain sustainable food production and can alleviate rural poverty.