The invasion of natural ecosystems by non-native plants is a growing problem of global concern. These species may cause problems by causing declines in native species or by changing the natural dynamics of, or ecological services provided by, ecosystems. Exotic plant invasions therefore incur massive control costs to alleviate these problems. Unfortunately, we lack sufficient data on most plant invasions to determine what controls invasion and what the subsequent impacts of those invasions may be. This project uses a long-term (45-year) data set documenting vegetation dynamics (changes in species diversity and abundances over time) in a series of abandoned agricultural fields in New Jersey to answer a series of questions about non-native plant invasions. Since land abandoned from agriculture is commonly heavily invaded by non-native species, it is an ideal model system to study invasions. The long-term nature of the data gives a much more realistic view of invasions, which typically occur over longer time spans than the relatively short (1-3 year) studies common in this field. The information gathered from these analyses should provide detailed explanations of the role non-native plant species that may be applied to invaded areas around the world. This project will provide training for at least six graduate (at the Master's degree level) and several undergraduate students over its duration. We also plan to develop educational resources that use the long-term data to allow students at a variety of levels to explore the dynamics of land recovering from agricultural practices and to educate students about exotic plant invasions. The information generated by this study should produce management strategies for addressing the control of plant invasions in a wide variety of systems.
