Chop and Drop
A chop-and-drop plant is one that produces a lot of biomass, which can be periodically pruned, pulled or cut back to ground level. Using the biomass as mulch, the organic matter then breaks down and feeds the soil
Deep tap roots;
Deep tap roots: Some chop and drop plants have deep tap roots, which drill beyond the reach of other roots, and they then accumulate trace minerals and nutrients from far beneath the surface. These elements build up in the plant, and when it is cut and used as mulch, all of those good minerals are then available to plants with roots closer to the surface.
Another chop-and-drop plant is the nitrogen-fixing legume. Nitrogen-fixing plants gather their own nitrogen from the air and store it in nodules in their roots. When a plant is pruned above the ground level, it releases nitrogen below the surface. This results in a natural fertilizing boost, both above and below the soil.