Background/Question/Methods The numbers of invasive plants are increasing in forests of the Midwestern United States, causing many ecological and economic problems. Buckthorn (Rhamnus cathartica) is a non-native shrub, which grows rapidly and shades out surrounding native plants. Therefore, it is important to better understand why buckthorn is so invasive in order to improve our methods of prevention and control. In order to test whether the release of shade-suppression would result in increased plant diversity, we used mechanical methods to remove the aboveground portion of the plant. In these 10x10 meter plots, we monitored plant diversity for the next two years, and we also monitored whether there was a shift in the type of mycorrhizal fungi.

Results/Conclusions After two years, there was not a significant difference between the control and removal plots for plant or fungal diversity, which suggests that the decline in plant diversity in the presence of buckthorn is not due to shade suppression alone. Other possible reasons that buckthorn may be so invasive include interactions with other invaders, and so we are currently following up these experiments with manipulations of earthworms and other invasives in these sites.