Leaf litter capture in the carnivorous pitcher plant, Sarracenia purpurea: a preliminary study

Diet breadth is a key life-history trait influencing range size, evolutionary trajectories, and ecosystem functioning. While diet breadth studies have traditionally been confined to animals, carnivorous plants provide an exciting conceptual extension to existing theory. We examine the possibility of diet breadth expansion in Sarracenia purpurea, a carnivorous pitcher plant, integrating field and greenhouse experiments with CHN analysis to quantify leaf litter consumption. Wild plants captured leaf detritus at levels comparable to insect prey. Pitchers fed leaf biomass in the field exhibited non-significant increases in foliar nitrogen, while the greenhouse experiment showed no effect of leaf litter. These results show that S. purpurea pitchers capture a substantial amount of leaf litter, but there is no clear evidence of nitrogen assimilation from this material. We found that short-term nitrogen acquisition from captured litterfall is minimal or absent in S. purpurea pitchers, especially relative to rapid nutrient assimilation from arthropod prey.