Two plots of restored prairie (IMAGE) Michigan State University Caption The boundary between two plots of prairie restored by MSU researchers, where the difference between them is the year they were planted. Native big bluestem grass in dominant in the plot to the left, while purple flowers belonging to non-native knapweed populate the plot on the right. Credit Lars Brudvig Usage Restrictions Can use with credit. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.