Green manure and mulch producer, N fertilizer
Thanks to its tolerance to coppicing and its N-fixing habit, Erythrina poeppigiana provides a high amount of green manure and mulch with high N value to the soil (Oyen, 1997). Poro was shown to improve the rate of soil mineralization (5.64 mg N/kg soil) in coffee plantations. It was suggested that the use of poro in coffee plantations could bring 100 kg N/ha with a variation from 56 to 555 kg/ha (Villarreyna Acuña et al., 2016).
Agroforestry species
Poro has many traits that make it a valuable agroforestry species. A thorny species, it can be planted as a living fence to keep livestock off the stand. However, it can be sensitive to strong winds and be uprooted (Oyen, 1997). In alley cropping systems and plantations, poro provides light shade. Once coppiced, its N-rich leaves produce high grade litter for the soil and its root nodules return high amounts of N to the neighbouring crops (cocoa, pepper, or grasses) (Fern, 2014; Oyen, 1997). In alley cropping systems, poro planted in dense hedgerows (1-2 m between trees), with wide alleys (6 - 8 m) between tree rows can sustain high bean yields (Fern, 2014). In Costa Rica, the use of poro with 2 maize crops per year was possible over 8 years without fertilization (Fern, 2014).