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.