Sphenostylis stenocarpa - (Hochst. Ex A.Rich.) Harms

Regional Crop  Management: Standard  Staple Crop: Protein  Agroforestry Services: Nitrogen

A plant of the tropics, where it is found at elevations up to 2,000 metres. It grows best in areas where annual daytime temperatures are within the range 23 - 29°c, but can tolerate 15 - 35°c[418 ]. It prefers a mean annual rainfall in the range 1,000 - 1,200mm, but tolerates 800 - 1,400mm[418 ]. Requires a dry period when flowering[300 ]. Prefers a position in full sun[418 ]. Grows best in a fertile, sandy soil[300 ]. Prefers a pH in the range 5.5 - 6, tolerating 4.5 - 7[418 ]. Although perennial, the plant is usually treated as an annual in cultivation[418 ]. Harvesting of the seedpods can commence about 5 months after sowing, and continue for another 2 months[300 ]. Tubers mature 7 - 8 months after sowing[300 ]. Optimum yields of the seed is 2 tonnes per hectare, and of the tubers 4 tonnes[418 ]. Plants are probably day length sensitive[300 ]. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[200 ]. When removing plant remains at the end of the growing season, it is best to only remove the aerial parts of the plant, leaving the roots in the ground to decay and release their nitrogen.

Carbon Farming

• Regional Crop  These crops have been domesticated and cultivated regionally but have not been adopted elsewhere and are typically not traded globally, Examples in this broad category include perennial cottons and many nuts and staple fruits.
• Management: Standard  Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.
• Staple Crop: Protein  (16+ percent protein, 0-15 percent oil). Annuals include beans, chickpeas, lentils, cowpeas, and pigeon peas. Perennials include perennial beans, nuts, leaf protein concentrates, and edible milks.
• Agroforestry Services: Nitrogen  Plants that contribute to nitrogen fixation include the legume family – Fabaceae.