According to a report published in the International Journal of Agricultural Sustainability in October 2011, a few hundred thousand African farmers with small land holdings have been able to substantially increase their crop yields by increasing their soil nutrients simply by planting “fertilizer trees”.
In Zambia, one of the five African countries where the farmers have planted the trees (according to the report), few farmers who have been using ‘fertilizer trees’ in their fields had an income between $233-$327 per hectare compared to $130 from the fields without the trees.
According to Wikipedia, Tephrosia, Sesbania, Gliricidia, and Faidherbiaalbida, all belonging to the Family Fabaceae, are known as Fertiliser trees.
Faidherbiaalbida, a tree native to Middle East and Africa has also been introduced in India and Pakistan. Apart from soil fertilisation due to their high N2 content, these trees are also used as food, fodder and medicine.
In some African countries like Zambia and Malawi, these trees have increased crop yields for farmers who plant them in a chequerboard fashion in the fields. Apart from being considered as a means of improving food security in the Africa, these trees also prevent the expansion of deserts and keep land arable in the arid regions of the continent.
The trees also increase water efficiency and prevent soil erosion helping reduce the loss of essential resources and soil nutrients, as their depletion is the main reason behind food production shortfalls in the African continent.