POSTER PRESENTER: http://tinyurl.com/2024WSC-Risdal TITLE: Evaluating the impacts of invasive cattail and European frog-bit on northern wild rice growth and germination ABSTRACT: Zizania palustris, northern wild rice, is an important plant for the ecology of Great Lakes coastal wetlands (GLCWs) and the culture of Native American tribes in the northern United States. Human development has severely limited its native range, and the ongoing invasion of Typha × glauca (hybrid cattail) and Hydrocharis morsus-ranae (European frog-bit) into lakes with native Z. palustris may further threaten surviving populations. There is little understanding of the effects of these invasives on Z. palustris, but the litter accumulation of Typha and the shading effect of floating Hydrocharis mats are suggested mechanisms impacting their populations. This two-week study, conducted at the University of Michigan Biological Station, addresses these impacts through a mesocosm experiment mimicking the effects of litter and shade on the germination and development of Z. palustris seedlings. Hydrocharis mats were simulated at three lighting cover levels (0%, 40%, and 80%), using floating circles cut to a uniform size, and Typha litter collected from nearby lakes was added in uniform amounts to a separate factor level. After the experiment, plant size, water chemistry, and dried seedling chemistry were evaluated to determine possible explanations for differences in plant development and nutrient distribution. This study determines the impact of light cover and plant litter accumulation on Z. palustris germination and growth. It also offers a better understanding of how the effects of two highly invasive plants can impact native plant survival and development. This knowledge can inform land management strategies for protecting and growing native Z. palustris populations throughout the Great Lakes basin. BIO: Alex Risdal is a current undergraduate sophomore at Loyola University Chicago. She works with Loyola's Team Typha as an undergraduate researcher. Alex's current work is determining the impacts of invasive European Frogbit (Hydrocharis morsus-ranae) and invasive cattail (Typha) on the growth and development of Wild Rice (Zizania palustris).