Attack of the 500-Pound Poison Ivy | OnEarth Magazine

http://www.onearth.org/blog/poison-ivy-climate-change

"If you want to deal with a problem, you have to know what size problem you're dealing with," Mycka says. "These plants are so powerful to start with, it doesn't take much of a touch from carbon to make it much worse."

That's exactly what scientists found when they planted poison ivy in an experimental forest at Duke University, piping in carbon dioxide to artificially raise the concentration of CO2 in the atmosphere to the levels it's expected to be by about 2050. The result, published in 2006: like other plants subjected to a high-CO2 environment, the poison ivy plants grew 150 percent bigger, with 153 percent higher concentrations of their oil, called urushiol.