The planting of mahogany (Swietenia macrophylla King) is severely limited by 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 recommendations. The present short communication reports on the results of an experimental study in which trees in 13 pairs were subjected to contrasting pruned/control (unpruned) treatments. Twenty-nine months after planting, pruned trees had significantly better values for form traits (p between 0.012 and 0.09) with no apparent difference in growth traits. It is concluded that pruning can mitigate the Hypsipyla problem. The generality of the results is briefly discussed. © 2001 Elsevier Science B.V.