ECO-FRIENDLY HABITAT RESTORATION: USING PHOTO-DEPRIVATION TO ERADICATE PHRAGMITES AUSTRALIS AND TO PROMOTE NATIVE PLANT SUCCESSION IN PIERMONT MARSH, NEW YORK

Piermont marsh is located approximately 40km north of the Battery in New York City. Over the past 60 years the invasive plant species Phragmites australis has out-competed the native vegetation, such as Schoenoplectus pungens, Typha latifolia, Spartina alternaflora, Spartina patens, Eleocharis parvula, and Hibiscus palustris, in accessing essential resources within the wetland. The resulting monoculture effectively limits the biodiversity of the marsh ecosystem. In an effort to manage the P. australis, the New York State Department of Environmental Conservation (NYSDEC) has studied use of sprayed herbicide throughout the marsh, which may pose a risk to the health of the surrounding biota. The local community of Piermont, NY is divided on the use of herbicide in the marsh and many citizens have come to embrace the aesthetics and perceived benefits of the invasive plant. The goal of our research is to study management of P. australis without the use of herbicide while at the same time providing a P. australis free area where the native species can regenerate and thrive. Photo-deprivation methods employed to eradicate the invasive plant have been implemented and studied in several marshes throughout the country, including nearby Constitution Marsh. In these practical applications P. australis was eradicated using only a permeable, woven black synthetic polymer material, commonly called geotextile, to fatally interrupt the plant’s photosynthetic ability to store sufficient carbohydrates during the summer growing season, subsequently causing rhizomal atrophy support the successful succession of the marsh’s native species once given a bare, Phragmites-free environment. By maintaining a protective buffer of rhizome-killing geotextile between the existing P. australis monoculture and our newly created P. australis free soil and expanding the remediated area bi-annually, our team hopes to create larger and larger areas of the marsh containing the original diversity of flora and fauna. Through careful monitoring and management, which may include judicious use of hand-applied herbicide for the occasional stray P. australis shoot, our team hopes to provide a viable, reproducible model for eco-friendly habitat rehabilitation.