A. ELLA, W.W. STÜR, G.J. BLAIR and C.N. JACOBSEN

Forage Research Project, Sub-Balai Penelitian Ternak, Gowa, South Sulawesi, Indonesia

Abstract

In a tropical environment with a distinct dry season the tropical tree legumes Calliandra calothyrsus, Sesbania grandiflora, Leucaena leucocephala and Gliricidia sepium were planted at a density of 5000, 10 000, 20 000 and 40 000 trees/ha and cut at intervals of either 6 or 12 weeks. An understorey grass, Panicum maximum cv. Riversdale, was established and this grass was harvested at the same time as the respective tree legume treatment.
Less than 50% of Sesbania grandiflora trees survived the regular cutting in this experiment while almost all trees of the other species survived. Tree leaf yields of the three surviving species were positively related to tree density in the wet season but less so in the dry season. The longer cutting interval produced a higher leaf yield in the first wet season harvest but not in later harvests when rainfall was lower.
In the wet season, the shorter cutting interval tended to produce higher grass yields in the higher densities while no differences between cutting intervals occurred in the lower tree densities. On the contrary, in the dry season grass yields were higher overall in the longer cutting interval and the higher tree densities.