Survey of Phragmites australis in Water Sources in Michigan’s Northern Lower Peninsula

Abstract

Understanding the distribution patterns of an invasive species is a first critical step toward controlling its spread into other ecosystems. Beginning in June of 2009, grassroots environmental protection organizations in northern Lower Michigan coordinated under the supervision of the Department of Natural Resources to address the presence of a Common Reed (Phragmites australis) subspecies that was introduced via the chain of Great Lakes in the 19th century and has since spread all the way to Wisconsin (Lindorth, 1957). Two genotypes of this grass-like flora are known to exist, one of which is native to North America and is found frequently in wetland ecosystems in the Midwest. The invasive subspecies, however, has proven to spread quickly into tidal or wetland ecosystems and displace native plant species. A total of 3971 meters of shoreline were found to be affected by Phragmites along a total of 74 kilometers of shoreline on the East Grand Traverse Bay of Lake Michigan as well as on Elk and Skegemog Lakes, nearly 5.4% of the total shore. During surveying, the GPS location of each stand of reeds was recorded, along with physical data including the length, breadth, approximate stem number and stem density of each population. All of 104 stands of the Phragmites australis found on the Grand Traverse Bay shoreline were found to be of the invasive subspecies while the mere three stands on the inland lake shorelines were identified as the native genotype. This survey supplied the scientific research, with respect to Phragmites stand distribution and size, necessary for a thorough grant application to the Michigan Department of Natural Resources to be composed by community leaders in Acme Township. Such a grant would help to fund chemical treatment of invasive Phragmites with aquatic herbicides if it was deemed necessary to do so to mitigate damage to the ecosystem.