Pruning and bark girdling or erva-mate (Ilex paraguariensis) aiming induction of basal sproutings

Abstract

The extrativism method, inappropriate management and the reduction of mate tree populations has resulted in the loss potencial of relevant specimens for future genetic improvement. Few are the techniques and studies, focused on the restoration of degraded mate tree plantations, in order to recover vegetative samples of mature trees. So, an experiment was installed in São Mateus Country, Paraná State-BR, in a mate weakened population whose trees aged approximately 40 years. The objective was to evaluate the efficiency of bark girdling, combined to different pruning intensities, on the sprouting at the base of the  trunk of weakened mate trees. A bark ring of 1 cm width, at 20 cm from the base, was removed. Additionally the crown was submitted to three pruning intensities: T0, control (no pruning); T40, 40 % crown pruning and T70, 70 % of crown pruning. The trees were grouped into five blocks, with six trees each, considered a block totalizing 30 mate trees. Mortality, number and length of the basal sprouts per tree were evaluated. After 270 days from the girdling procedure no mortality has been detected. The 70 % pruning intensity induced a greater number of sprouts per plant. Even being weakened mate trees, showed high healing capacity of the removed bark ring, indicating the technical