Figure 1. The northern pitcher plant traps prey in its tubelike pitcher structure where a suite of microorganisms digests prey and extracts nutrients needed for plant growth.
CARNIVOROUS PLANTS OBTAIN NUTRIENTS needed for growth through the breakdown of insects, microbes, and small amphibians (see sidebar). The most widely distributed carnivorous plant in North America is the northern pitcher plant (Sarracenia purpurea L., fig. 1, above), whose range stretches from northern Canada to the midwestern United States, and along the eastern U.S. coast south to the Gulf of Mexico. This species lives primarily in isolated, low-nutrient sphagnum moss bog and poor fen wetlands (fig. 2). Though individual populations are large, typically containing more than 100 plants, the species is in decline because of the loss of its specialized wetland habitat. The wetlands that host the northern pitcher plant are in a perilous position, often drained for development, mined for Sphagnum for the horticultural trade, or degraded by inputs of road salt and lawn and agricultural fertilizer runoff. Additionally, carnivorous plant enthusiasts prize this species and threaten population survival through overcollection. As habitat and populations of the northern pitcher plant become increasingly rare, state and federal agencies are showing greater interest in conserving habitat and restoring plant populations.
Indiana Dunes National Lakeshore protects one of the few remaining populations of northern pitcher plant in the state (NatureServe 2007) (fig. 3). This population, located at the Indiana Dunes Pinhook Bog property, is isolated within an extensively developed landscape along the southern rim of Lake Michigan east of Gary, Indiana. Consequently, the national lakeshore has experienced declining populations of the northern pitcher plant. Scientifically informed management to restore this species is crucial to its survival in this and other fragmented ecosystems. Planning and implementing successful restoration of plant populations requires knowledge about how the plant functions ecologically, how it reproduces, what environmental qualities it requires, and how populations relate to each other genetically. Reestablishment of the pollination services provided by bees in Pinhook Bog will sustain the reproductive potential and genetic resilience of pitcher plants (Dixon 2009).
Karberg, J. M., J. Marburger, and M. R. Gale. 2009. Exploring the influence of genetic diversity on pitcher plant restoration in Indiana Dunes National Lakeshore. Park Science 26(2): 30–35.
Available at http://www.nature.nps.gov/ParkScience/archive/PDF/Article_PDFs/ParkScience26(2)Fall2009_30-35_Karberg_et_el_2640.pdf.