The effectiveness of pruning in mitigating Hypsipyla grandella attack on young mahogany (Swietenia macrophylla King) trees

The planting of mahogany (Swietenia macrophylla King) is severely limited b y the attack of the: shoot-borer Hypsipyla grandella. Pruning is sometimes advocated as one means of controlling and/or mitigating shoot-borer attack. However. there appears to be no published experimental support for such re commendations. The present short communication reports on the results of an experimental study in which trees in 13 pairs were subjected to contrastin g pruned/control (unpruned) treatments. Twenty-nine months after planting, pruned trees had significantly better values for form traits (p between 0.0 12 and 0.09) with no apparent difference in growth traits. It is concluded that pruning can mitigate the Hypsipyla problem. The generality of the resu lts is briefly discussed. (C) 2001 Elsevier Science B.V. All rights reserve d.