The impacts of white-tailed deer (Odocoileus virginianus) herbivory on the forage quality of forest vegetation

White-tailed deer (Odocoileus virginianus) are abundant across North America. Deer impact ecosystems, both directly and indirectly. These impacts are driven by the foraging preferences of deer. The energy, protein, mineral, fiber, and secondary metabolite content of plants are important factors that inform the selective herbivory of deer. I examined the interactions between forage quality and deer impacts in northern Wisconsin using deer exclosures. I examined the forage quality of four focal species (Acer saccharum, Maianthemum canadense, Dryopteris intermedia and Carex pensylvanica) in both control and exclosure plots. Forage quality parameters measured were energy, protein, ash, phosphorus, silica, fiber, and saponins. I found that deer herbivory did not uniformly decrease the forage quality within individual species. This study provides preliminary support for a predicted increase in low forage quality plants in response to heavy deer herbivory. Further research is necessary to support this trend, including a focus on defensive secondary metabolites