Climate change's impact on invasive plants in Western US may create restoration opportunities

EurekAlert: A new study by researchers at Princeton University's Woodrow Wilson School of Public and International Affairs has found that global climate change may lead to the retreat of some invasive plant species in the western United States, which could create unprecedented ecological restoration opportunities across millions of acres throughout America. At the same time, global warming may enable other invasive plants to spread more widely.

The study, "Climate change and plant invasions: restoration opportunities ahead?", was co-authored by Bethany Bradley, a biogeographer, Michael Oppenheimer, a geoscientist, and David Wilcove, a conservation biologist, at Princeton's Woodrow Wilson School, and is published in the journal Global Change Biology. The article is accessible online at http://www3.interscience.wiley.com/journal/121521769/abstract.

The researchers assessed the relationship between climate change and the distribution of five prominent invasive plants in the western United States – known colloquially as the "kudzus of the West" – cheatgrass; spotted knapweed; yellow starthistle; tamarisk; and leafy spurge. Such plants are defined as invasive because they were brought into this country from other lands and now dominate and alter ecosystems in ways that threaten native wildlife, agriculture, and ranching. All have greatly expanded their ranges in recent decades in the western U.S., causing millions of dollars in damage to farmlands and rangelands. Invasive plants are increasingly expensive to control, and it is widely believed that global warming will make the problem worse.

But Bradley and her co-authors find that global warming may also reduce the competitiveness of some invasive plants if conditions become climatically unsuitable to the weeds, "creating opportunities for restoration in areas currently dominated by intractable invasive species," according to the study.

A bumblebee voguing on spotted knapweed, shot by Cody Hough, college student and photographer in the Michgian area, Wikimedia Commons, under the Creative Commons Attribution ShareAlike 3.0 License