Intercropping is advantageous in Africa, particularly in relation to improving maize yields in the sub-Saharan region. Use relies upon the nitrogen-fixing tree species "Sesbania sesban, Tephrosia vogelii, Gliricidia sepium" and "Faidherbia albida". In one example, a ten-year experiment in Malawi showed that, by using the fertilizer tree Gliricidia ("Gliricidia sepium") on land on which no mineral fertilizer was applied, maize yields averaged 3.3 tonnes per hectare as compared to one tonne per hectare in plots without fertilizer trees or mineral fertilizers.