Production of leaves and shoots on branches of mesquite shrubs which had been girdled by the mesquite twig girdler (Oncideres rhodisticta) was compared with the production of unaffected branches on girdled and ungridled shrubs. We made similar comparisons on mesquite which had been subjected to simulated girdling or terminal node destruction of 40-80 per cent of the branches. There was no significant difference in shoot and leaf growth in either natural or simulated damaged plants compared to controls. These studies suggest that the timing of the activity of stem-destroying insects may be important in minimizing damage to the plant.