Invasive plant rhizome production and competitiveness varies based on neighbor identity

Smith, Atwater, Kim, Haak & Barney

Johnsongrass encounters many different competitors in its invasive range. We see evidence that agricultural populations, which compete primarily with crops, and populations in waste areas, which compete primarily with one another, differ phenotypically and genetically. In this study we found evidence that within-species competition may be much stronger than competition with crops. Furthermore, Johnsongrass from croplands competed differently than Johnsongrass from waste areas.