Fertilizer tree

Fertilizer trees are used in agroforestry to improve the condition of soils used for farming. As woody legumes, they capture nitrogen from the air and put it in the soil through their roots and falling leaves. They can also bring nutrients from deep in the soil up to the surface for crops with roots that cannot reach that depth. Fertilizer trees are further useful for preventing fertilizer erosion, soil degradation and related desertification, and improving water usage for crops.

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