Sedges are perennial herbs that resemble grasses, with long, narrow leaves and small, unisexual flowers that are mostly wind pollinated. Sedges have a worldwide distribution but are most diverse in North America and eastern Asia. They grow in a wide range of habitats, and many species are restricted to particular local environments. Sedges play important roles in wetland succession, peat development, and stabilization of slopes, and they provide food and shelter to wildlife. Despite their ecological importance, their taxonomy is in poor condition, with large numbers of species described on the basis of only a few, often unreliable morphological features. Graduate student Robert Naczi under the guidance of faculty sponsor Anton Reznicek at the University of Michigan is studying the taxonomy and evolution of sedges of the genus Carex section Griseae, a group of about 17 species native to eastern North America. Data from the study of morphology, anatomy, and chromosomes will be used to delimit coherent species, and these will be mapped against soil substrate and geographical range. Comparisons with other sedge groups will be made to hypothesize a likely phylogeny for the group, for future testing with molecular data. The results of the project should be a model investigation useful to systematists and ecologists worldwide who are interested in the biology and evolution of sedges.
