On a level field: the utility of studying native and non-native species in successional systems

Questions: How do successional systems contribute to our understanding of plant invasions'? Why is a community-level approach important in understanding invasion? Do native and non-native plant species differ in their successional trajectories within communities? Location: Northeastern United States, in the Piedmont region of New Jersey. Previously farmed since the 1700s, ten fields were experimentally retired from agriculture beginning in 1958. Methods: Fifty years of permanent plot data were used to quantify the Population demographics of the 84 most abundant species during succession. These measures were then used to compare native, non-native and non-native invasive species' Population dynamics in succession. Results: Once basic life-history characteristics were accounted for, there were no differences in the Population dynamics of native, non-native, and non-native invasive plant species. However, the species pool in this study was biased towards ruderal species, which largely constrained non-native species to early Succession. Conclusion: Successional systems are crucial to our understanding of invasions as they constrain all species to the role of colonizer. By focusing on the whole community, rather than on individual problematic species, we found no systematic differences between native and non-native species. Thus, knowing simple life-history information about a species would be much more useful in setting management priorities than where the species originated.