MS Thesis Defense | Hayley Edlund

I investigated the effects of agricultural pesticides and different seed mixes on resulting restoration plant community composition and diversity. I found that seed mix diversity was the most important factor in explaining current variation in plant community attributes, counteracting legacy effects of agriculture. Nonideal starting conditions at a restoration site may be overcome with a high diversity native seed mixture, especially including native forbs which greatly contribute to diversity. I also investigated the efficacy of triclopyr herbicide, nitrogen fertilizer, and the addition of native seed mixes for controlling invasive species Lespedeza cuneata in restored tallgrass prairie. Herbicide was the most effective treatment for reducing L. cuneata cover, but it also led to an increase in cover by other nonnative species. My results indicate that successful prairie restoration will require consistent manager efforts, beginning with development of diverse seed mixes and continuing to monitor, prevent, and control invasive species.