PLASTIC GROWTH RESPONSES TO SIMULATED HERBIVORY

Plants rely on phenotypic plasticity to maintain performance and survive in changing environments. Stress such as herbivory has the potential to cause short-and long-term changes to a plant's phenotype. In response to simulated herbivory by clipping, plants either may show lower growth and fecundity or may overcompensate and exceed the size and fecundity of undamaged individuals. This study examined the short-and long-term responses to the timing and frequency of clipping in Barbarea vulgaris. In the greenhouse, clipping resulted in elevated growth rates, and individuals eventually matched the size of undamaged individuals. In the field, clipping had negligible effects on size or fitness components. Aboveground clipping also reduced the belowground biomass. One possible explanation for the size convergence and equal fecundity despite clipping 50% of the leaves is that the belowground biomass supports the regrowth of the aboveground biomass. Stored belowground resources allowed plants to regenerate lost photosynthetic tissue. These results illustrate the ability of B. vulgaris to tolerate clipping. Regardless of the timing or frequency of clipping, plants that experienced biomass removal displayed remarkable plasticity and were able to maintain performance relative to undamaged plants.