Ecologists call for screening imported plants to prevent a new wave of invasive species

University of Massachusetts Amherst Office of News and Media Relations: A recent analysis led by ecologist Bethany Bradley at the University of Massachusetts Amherst suggests that climate change predicted for the United States will boost demand for imported drought- and heat-tolerant landscaping plants from Africa and the Middle East. This greatly increases the risk that a new wave of invasives will overrun native ecosystems in the way kudzu, Oriental bittersweet and purple loosestrife have in the past, members of the international team say.

...Bradley and colleagues recommend that U.S. authorities adopt proactive management practices, in particular pre-emptive screening of nursery stock before new plants are imported, to prevent such an explosion of new invasives. Their conclusions appear in an early online edition of the Feb. 1 issue of Frontiers in Ecology and the Environment.

As the UMass Amherst environmental conservationist and lead author explains, the U.S. Department of Agriculture (USDA) has proposed the Not Authorized Pending Pest Risk Analysis (NAPPRA) rule to regulate the industry. The rule would require importers to notify the USDA of proposed imports. USDA scientists would then conduct a timely risk assessment and issue a recommendation to allow or curtail the import.

"Our study identifies climate change as a risk, which combined with other factors is likely to increase demand for imported heat- and drought-tolerant plants, but this emerging threat is one that policy can effectively address," Bradley says. "The USDA has tools to reduce import risk and we advocate that now is the time put them in place. Pre-import screening has been tested in Australia for about 10 years now and it’s not foolproof, but it seems to have done a good job of separating the really bad import ideas from more benign introductions."...

Purple loosestrife (Lythrum salicaria), Laird, Ontario, shot by Fungus Guy, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license