Leaf litter capture in the carnivorous pitcher plant, <em>Sarracenia purpurea</em>: 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. Methods This dataset describes the capture, digestion, and utlization of leaf litter by the carnivorous pitcher plant Sarracenia purpurea. It includes observational data on the incidence of leaf litter within wild S. purpurea pitchers over time, ammonia measurements quantifying the release of nitrogen from leaf litter and insect prey into pitcher fluids, and percent foliar nitrogen and carbon measurments of pitchers experimentally fed leaf litter or insect biomass in both field and greenhouse contexts. It also includes S. purpurea growth metrics (rosette diameter, pitcher number, leaf senescence) and inquiline survivorship data as a response to experimental diet treatments. Fluid ammonia levels were measured using 0-6.0 mg/L Ammonia Test Strips (Hach, Loveland, Colorado, United States), and nitrogen and carbon concentrations were measured using CHN combustion analysis.