Relation between management and leucaena (Leucaena leucocephala) to prevent its transformation into an invasive plant.
The effect of management was evaluated to prevent leucaena becoming an invasive plant. For five years, the evolution of two systems was studied: (1) tree legume Leucaena leucocephala cv. Peru in silvopastoral system, where it occupied 100% of the area, associated with Brachiaria brizantha cv. Marandú for cattle fattening; (2) tree legume Leucaena leucocephala cv. Peru, where it occupied 100% of the area, associated with Brachiaria brizantha cv. Marandú without being grazed. A random block design was applied, with five replications. Indicators in the leucaena-brachiaria system with animal grazing were better, at the beginning and at the end of the experiment, with a decrease in the depopulation of 1 plant/m2 (P=0.0012), higher grass population 11.2/m2 (P=0.0014) and low presence of weeds 1 plant/m2 (P=0.0039), which was better in the system without grazing. Leucaena component had a different performance, according to the studied system. In the system under grazing, yield of brachiaria base grass was always superior (2.2 and 3.0 t/ha DM) with respect to the non-managed system, at the beginning (P=0.0028) and at the end of the experimental stage. The same happened with the presence of natural grass 0.40 t/ha DM (P=0.0011), which disappeared at the end. Weeds had a higher presence in the non-managed area 0.31 t/ha DM (P=0.0101) at the beginning of the study. It is concluded that the technological proposal for the management of systems with Leucaena leucocephala in silvopastoral systems is a functional and feasible option to apply so that this species does not become invasive.