Seedling resistance, tolerance and escape from herbivores: insights from co-dominant canopy tree species in a resource-poor African rain forest

Although plants can reduce the impacts of herbivory in multiple ways, these defensive traits are often studied in isolation and an understanding of the resulting strategies is incomplete. In the study reported here, empirical evidence was simultaneously evaluated for the three main sets of traits available to plants: (1) resistance through constitutive leaf traits, (2) tolerance to defoliation, and (3) escape in space, for three caesalpiniaceous tree species Microberlinia bisulcata, Tetraberlinia bifoliolata and T. korupensis, which co-dominate groves within the lowland primary rain forest of Korup National Park (Cameroon). Mesh cages were placed around individual wild seedlings to exclude insect herbivores at 41 paired canopy-gap and understorey locations. After following growth and survival for c. 2 yr, caged and control treatments were removed, leaves harvested to determine nutrient and phenolic concentrations, leaf mass per area estimated, and seedling performance in gaps followed f...