Effects of tree species and planting density on the total yield of an agroforestry system in the Brazilian Cerrado

This study aimed to evaluate the effects of spacing and population density of three tree species on the primary yield of an agroforestry system in the Cerrado. The experiment was conducted in the experimental area of the State University of Goias, Sao Luis de Montes Belos, Brazil. The experiment was designed to assess the effects of tree species, density, and spacing in a factorial scheme of 3 x 2 x 3, totaling 18 treatments with two tree rows each. The tree species assessed were Corymbia citriodora (seedlings), Eucalyptus cloeziana (seedlings), and an Eucalyptus urophylla clone. The trees were planted in single and triple rows (Trees planted in single and triple rows, varying density). In the first year of the experiment, maize (Zea mays) and Crotalaria juncea were sown, maize and Marandu palisadegrass (Uroclhoa brizantha cv. Marandu) in the second year, and a monoculture of Marandu palisadegrass during the third and fourth years. Due to the larger tree-covered area, the arrangement in triple rows reduced maize yield by 36% in the first year, silage yield by 40% in the second year, and pasture yield by approximately 30%. Reducing tree density is crucial to ensure the functionality of the agroforestry system.