Date of Award

January 2015

Degree Type


Degree Name

Master of Science (MS)


Forestry and Natural Resources

First Advisor

Songlin Fei

Committee Member 1

Bryan C Pijanowski

Committee Member 2

Jeffery H Holland


Understanding large-scale invasion patterns and processes is essential for effective and proactive management of exotic species that have caused significant ecological and economic damages. While many studies have focused on specific habitats and species, my research is aimed at the broad-scale patterns of expansion during the course of the past two centuries. I use long-term herbarium specimens to recreate the spatiotemporal distributions of 29 invasive plant species within the eastern United States. The emerging spatial patterns reveal species’ expansion through a continuum of radial expansion, long distance jump dispersals, and range infilling. This study identifies a set of metrics that is able to quantitatively measure the changing morphology of the spatiotemporal patterns that emerge at macroscales. Utilizing graph and network theory I additionally reconstructed the most plausible processes of the invasion expansion. Results show that invasion is closely facilitated by human activity and there are considerable commonalities of distribution and dispersal patterns among invasive plant species.