THE DEPENDENCE OF HERBIVORY ON GROWTH-RATE IN NATURAL PLANT-COMMUNITIES

1. The hypothesis that herbivory pressure (defined as the per cent of the photosynthetic tissue biomass and production consumed daily by her bivores) increases with increasing plant growth rate was tested. The b asis for the test was a compilation of 56 published reports on biomass , production and herbivory, from a wide range of aquatic and terrestri al plant communities. 2. Herbivory was independent of ecosystem primar y production and the fraction of plant production and biomass daily co nsumed by herbivores increased as the 0.6 and 1-6 power of plant turno ver rate, respectively. 3. These results suggest that the tendency of fast-growing plants to support lower biomass of photosynthetic tissues than slow-growing ones can be accounted for by the tendency of herbiv ore control of plant biomass and production to increase with increasin g plant growth rate. 4. It is concluded that herbivory should be most important as a control mechanism for fast-growing plant communities, w hereas it represents but a modest percentage of losses of photosynthet ic tissues of slow-growing plants.