Planting cover crops to simultaneously establish native prairie seedlings and prevent weed invasion is an increasingly common management practice. The idea is based on the assumptions that the cover plant will act as a nurse plant to prairie seedlings and that it will have a positive effect on seedling recruitment by suppressing weeds and by lowering the harmful effects of high evaporation and light availability. Cover crops could also potentially reduce the amount of soil erosion that occurs during planting. However, the evidence supporting the benefits of cover crops is mostly anecdotal and has been challenged. Clearly, there is a need for further scientific evidence on the efficacy of cover plants, their possible facilitative or competitive effects on prairie seedlings, as well as how these processes work. Of particular interest is whether the nurse plant effect is caused by light suppression or water uptake.