Time-Dependent Impacts of Cattail Invasion in a Great Lakes Coastal Wetland Complex

The aggressive cattail species Typha X glauca and Typha angustifolia have established in wetlands across the Great Lakes region, decreasing native plant diversity and altering environmental conditions. We relied on a parallel study in which 80 years of historical aerial photographs from a large Lake Michigan wetland complex were used to map the spread and determine the age of invasive cattail stands. Floristic, edaphic, and environmental data were collected from plots across an invasion-age gradient. Compared with reference uninvaded sites, litter mass more than doubled within 10 years of invasion ( P