Volume 1, Issue 2 - Winter 2008
The Kudzu Factor
EFETAC scientist investigates plants' invasive potential
When EFETAC ecologist Qinfeng Guo began his career in Santa Monica, CA, invasive species like kudzu did not seem like a big deal. After all, the Santa Monica Mountains are covered in exotic and indigenous herbs that are native to Chile and the Mediterranean and thrive in a climate similar to the California Mountains. Many foreign or exotic species are not considered invasive—Mediterranean olive trees dropping their fruit on California sidewalks are a common occurrence, but these species are not spreading along the highways and into native forests, like kudzu has taken over the South.
Right: EFETAC scientist Qinfeng Guo is surrounded by invasives research that he consults as he investigates plants' invasive potential.
In the southeastern U.S., kudzu grows out of control, enveloping entire forests. Its leaves reach over the tops of the trees and unfurl in the hot southern sun. This drastic difference in growth led Guo to question which environmental factors welcome exotic plants to live harmoniously in their native ecology, and allow them to grow, spread, and become invasive in similar climates.
Guo reasons that "most invasive plants have greater dispersibility, higher growth and reproduction rates, and greater compatibility. Some plants escape from their natural enemies, strong competitors, and predators after they are introduced." Guo’s interest was piqued by this complex issue, and he soon found himself leaving California to continue his studies with EFETAC in Asheville, NC.
When Guo arrived in the Southeast, a noticeable hot spot for invasive species, he turned his attention to researching quantifiable factors that create an ideal climate and habitat for invasive exotics to thrive. Guo’s immediate challenge was creating a plan to find the connections. "Most of the data on invasive plants are scattered and disconnected," Guo says. He soon recognized that the compilation and collection of this data would require an extensive collaborative effort to develop.
Guo began collecting information on existing plants in their native and introduced range, including the climate regime in the originating country and current location. He even collected data on the ethnobotanical—or relationship between plants and people—history for each species. Until recently, Guo used a series of spreadsheets to organize his huge amount of data. Through collaboration with the University of North Carolina Asheville’s National Environmental Modeling and Analysis Center (NEMAC), Guo is updating his technique and migrating his data to a relational database built by Joe Brownsmith (Department of Computer Science/NEMAC). Brownsmith encourages scientists to consider working with relational databases rather than spreadsheets. He believes that although a relational database is more work initially to create, it will eventually allow Guo to gain a greater understanding of the relationships among groups of data, such as regional soil pH, climate factors such as moisture and heat, and existence of predators.
This large project is only in its second year and has many collaborators from the U.S. and China, Guo says, with research assistants aiding in data input. While he hopes the database will be finished in another two years, Guo plans updates as information becomes available. When asked how the database will benefit others, Guo simply states "when complete, it should improve our understanding of species invasiveness."