The researchers studied how different tropical green manure plants break down and release nutrients over time. They looked at jack bean, pigeon pea, dwarf mucuna, and sunn hemp. Sunn hemp and pigeon pea decomposed slower and released less carbon, nitrogen, potassium, and magnesium. Jack bean decomposed faster and released more nutrients. In general, jack bean and dwarf mucuna are good for quickly supplying nutrients to crops, while sunn hemp and pigeon pea are better for longer-lasting soil cover.