Mixed Plantations of Eucalyptus and Leguminous Trees Enhance Biomass Production

Book excerpt: Two Eucalyptus species-E. saligna Sm. and E. grandis Hill-are especially favored in Hawaii for wood, fiber, and fuel production because of their quick growth and high yields. Their growth is limited, however, on many sites by low levels of available nitrogen. Supplemental nitrogen can be provided by nitrogen-fixing plants, such as legumes. A test was conducted to determine whether planting two leguminous species-Acacia melaxylon R. Br. and Albizia facataria (L.) Fosberg-could increase biomass production. Results after 65 months suggest that Eucalyptus growth can be increased substantially by planting the species in mixture with leguminous trees. Total biomass production was much greater in the mixed species plantations than in the pure Eucalyptus plantation.