GRAZING AS A MANAGEMENT TOOL FOR CONTROLLING PHRAGMITES AUSTRALIS AND RESTORING NATIVE PLANT BIODIVERSITY IN WETLANDS

Abstract

This study examined the feasibility of grazing as a sustainable and low-impact means of controlling Phragmites. In addition, this study examined whether grazing of Phragmites by large herbivores (goats) in a wetland affects soil and soil water nutrient pools, and thus how grazing might affect nutrient export from the wetland. An isolated, created wetland at USDA's Beltsville Agricultural Research Center (BARC) in Beltsville, MD was divided into four grazed and four ungrazed plots. Two rounds of grazing significantly reduced Phragmites height, stem count, and biomass and increased some measures of plant diversity. Grazing significantly elevated soil water total nitrogen and total phosphorus levels and reduced soil water-soluble phosphorus levels. The nutrient pool analysis indicates that grazing reduced the fertility of the system. The results of this study will inform the development of an alternative, sustainable approach to controlling Phragmites that integrates the local agricultural community while benefiting the local ecology.